---

lib/header.c

Go to the documentation of this file.

#undef  REMALLOC_HEADER_REGION
#define _DEBUG_SWAB 1
#define _DEBUG_INDEX 1

/* RPM - Copyright (C) 1995-2000 Red Hat Software */

/* Data written to file descriptors is in network byte order.    */
/* Data read from file descriptors is expected to be in          */
/* network byte order and is converted on the fly to host order. */

#include "system.h"

#if !defined(__LCLINT__)
#include <netinet/in.h>
#endif  /* __LCLINT__ */

#include <header.h>

#include "debug.h"

/* XXX avoid rpmlib.h, need for debugging. */
/*@observer@*/ const char *const tagName(int tag)       /*@*/;

/*
 * Teach header.c about legacy tags.
 */
#define HEADER_OLDFILENAMES     1027
#define HEADER_BASENAMES        1117

#define INDEX_MALLOC_SIZE 8

#define PARSER_BEGIN    0
#define PARSER_IN_ARRAY 1
#define PARSER_IN_EXPR  2

static unsigned char header_magic[8] = {
        0x8e, 0xad, 0xe8, 0x01, 0x00, 0x00, 0x00, 0x00
};

static int typeSizes[] =  { 
        0,      
        1,      
        1,      
        2,      
        4,      
        -1,     
        -1,     
        1,      
        -1,     
        -1      
};

struct entryInfo {
    int_32 tag;                 
    int_32 type;                
    int_32 offset;              
    int_32 count;               
};

#define REGION_TAG_TYPE         RPM_BIN_TYPE
#define REGION_TAG_COUNT        sizeof(struct entryInfo)

#define ENTRY_IS_REGION(_e)     ((_e)->info.tag < HEADER_I18NTABLE)
#define ENTRY_IN_REGION(_e)     ((_e)->info.offset < 0)

struct indexEntry {
    struct entryInfo info;      
/*@owned@*/ void * data;        
    int length;                 
    int rdlen;                  
};

struct headerToken {
/*@owned@*/ struct indexEntry *index;   
    int indexUsed;              
    int indexAlloced;           
    int region_allocated;       
    int sorted;                 
    int legacy;                 
/*@refs@*/ int nrefs;   
};

struct sprintfTag {
    headerTagTagFunction ext;   
    int extNum;
    int_32 tag;
    int justOne;
    int arrayCount;
/*@kept@*/ char * format;
/*@kept@*/ char * type;
    int pad;
};

struct extensionCache {
    int_32 type;
    int_32 count;
    int avail;
    int freeit;
/*@owned@*/ const void * data;
};

struct sprintfToken {
    enum {
        PTOK_NONE = 0,
        PTOK_TAG,
        PTOK_ARRAY,
        PTOK_STRING,
        PTOK_COND
    } type;
    union {
        struct {
            /*@only@*/ struct sprintfToken * format;
            int numTokens;
        } array;
        struct sprintfTag tag;
        struct {
            /*@dependent@*/ char * string;
            int len;
        } string;
        struct {
            /*@only@*/ struct sprintfToken * ifFormat;
            int numIfTokens;
            /*@only@*/ struct sprintfToken * elseFormat;
            int numElseTokens;
            struct sprintfTag tag;
        } cond;
    } u;
};

static int dataLength(int_32 type, const void * p, int_32 count, int onDisk)
        /*@*/
{
    int length = 0;

    switch (type) {
    case RPM_STRING_TYPE:
        if (count == 1) {       /* Special case -- p is just the string */
            length = strlen(p) + 1;
            break;
        }
        /* This should not be allowed */
        fprintf(stderr, _("dataLength() RPM_STRING_TYPE count must be 1.\n"));
        exit(EXIT_FAILURE);
        /*@notreached@*/ break;

    case RPM_STRING_ARRAY_TYPE:
    case RPM_I18NSTRING_TYPE:
    {   int i;

        /* This is like RPM_STRING_TYPE, except it's *always* an array */
        /* Compute sum of length of all strings, including null terminators */
        i = count;

        if (onDisk) {
            const char * chptr = p;
            int thisLen;

            while (i--) {
                thisLen = strlen(chptr) + 1;
                length += thisLen;
                chptr += thisLen;
            }
        } else {
            const char ** src = (const char **)p;
            while (i--) {
                /* add one for null termination */
                length += strlen(*src++) + 1;
            }
        }
    }   break;

    default:
        if (typeSizes[type] != -1) {
            length = typeSizes[type] * count;
            break;
        }
        fprintf(stderr, _("Data type %d not supported\n"), (int) type);
        exit(EXIT_FAILURE);
        /*@notreached@*/ break;
    }

    return length;
}

static int regionSwab(struct indexEntry * entry, int il, int dl,
                const struct entryInfo * pe, char * dataStart, int regionid)
{
    char * tprev = NULL;
    char * t = NULL;
    int tdel, tl = dl;

    for (; il > 0; il--, pe++) {
        struct indexEntry ie;
        int_32 type;

        ie.info.tag = ntohl(pe->tag);
        ie.info.type = ntohl(pe->type);
        ie.info.count = ntohl(pe->count);
        ie.info.offset = ntohl(pe->offset);
        ie.data = t = dataStart + ie.info.offset;
        ie.length = dataLength(ie.info.type, ie.data, ie.info.count, 1);
        ie.rdlen = 0;

assert(ie.info.type >= RPM_MIN_TYPE && ie.info.type <= RPM_MAX_TYPE);

        if (entry) {
            ie.info.offset = regionid;
            *entry = ie;        /* structure assignment */
            entry++;
        }

        /* Alignment */
        type = ie.info.type;
        if (typeSizes[type] > 1) {
            unsigned diff;
            diff = typeSizes[type] - (dl % typeSizes[type]);
            if (diff != typeSizes[type]) {
                dl += diff;
            }
        }
        tdel = (tprev ? (t - tprev) : 0);
        dl += ie.length;
        tl += tdel;
        tprev = (ie.info.tag < HEADER_I18NTABLE)
                ? dataStart : t;

        /* Perform endian conversions */
        switch (ntohl(pe->type)) {
        case RPM_INT32_TYPE:
        {   int_32 * it = (int_32 *)t;
            for (; ie.info.count > 0; ie.info.count--, it += 1)
                *it = htonl(*it);
            t = (char *) it;
        }   break;
        case RPM_INT16_TYPE:
        {   int_16 * it = (int_16 *) t;
            for (; ie.info.count > 0; ie.info.count--, it += 1)
                *it = htons(*it);
            t = (char *) it;
        }   break;
        default:
            t += ie.length;
            break;
        }
    }
    tdel = (tprev ? (t - tprev) : 0);
    tl += tdel;
    if (tl > dl)
        dl = tl;
    return dl;
}

static void copyEntry(const struct indexEntry * entry, /*@out@*/ int_32 * type,
        /*@out@*/ const void ** p, /*@out@*/ int_32 * c, int minMem)
                /*@modifies *type, *p, *c @*/
{
    int_32 count = entry->info.count;

    if (p)
    switch (entry->info.type) {
    case RPM_BIN_TYPE:
        /* XXX this only works for HEADER_IMMUTABLE */
        if (ENTRY_IS_REGION(entry)) {
            int_32 * ei = ((int_32 *)entry->data) - 2;
            struct entryInfo * pe = (struct entryInfo *) (ei + 2);
            char * dataStart = (char *) (pe + ntohl(ei[0]));
            int_32 rdl = -entry->info.offset;   /* negative offset */
            int_32 ril = rdl/sizeof(*pe);

            count = 2 * sizeof(*ei) + (ril * sizeof(*pe)) +
                        entry->rdlen + REGION_TAG_COUNT;
            *p = xmalloc(count);
            ei = (int_32 *) *p;
            ei[0] = htonl(ril);
            ei[1] = htonl(entry->rdlen + REGION_TAG_COUNT);
            pe = (struct entryInfo *) memcpy(ei + 2, pe, (ril * sizeof(*pe)));
            dataStart = (char *) memcpy(pe + ril, dataStart,
                                        (entry->rdlen + REGION_TAG_COUNT));

            (void) regionSwab(NULL, ril, 0, pe, dataStart, 0);
        } else {
            count = entry->length;
            *p = (!minMem
                ? memcpy(xmalloc(count), entry->data, count)
                : entry->data);
        }
        break;
    case RPM_STRING_TYPE:
        if (count == 1) {
            *p = entry->data;
            break;
        }
        /*@fallthrough@*/
    case RPM_STRING_ARRAY_TYPE:
    case RPM_I18NSTRING_TYPE:
    {   const char ** ptrEntry;
        int tableSize = count * sizeof(char *);
        char * t;
        int i;

        if (minMem) {
            *p = xmalloc(tableSize);
            ptrEntry = (const char **) *p;
            t = entry->data;
        } else {
            t = xmalloc(tableSize + entry->length);
            *p = (void *)t;
            ptrEntry = (const char **) *p;
            t += tableSize;
            memcpy(t, entry->data, entry->length);
        }
        for (i = 0; i < count; i++) {
            *ptrEntry++ = t;
            t = strchr(t, 0);
            t++;
        }
    }   break;

    default:
        *p = entry->data;
        break;
    }
    if (type) *type = entry->info.type;
    if (c) *c = count;
}

struct headerIteratorS {
    Header h;           
    int next_index;     
};

HeaderIterator headerInitIterator(Header h)
{
    HeaderIterator hi = xmalloc(sizeof(struct headerIteratorS));

    headerSort(h);

    hi->h = headerLink(h);
    hi->next_index = 0;
    return hi;
}

void headerFreeIterator(HeaderIterator iter)
{
    headerFree(iter->h);
    free(iter);
}

int headerNextIterator(HeaderIterator hi,
                 int_32 * tag, int_32 * type, const void ** p, int_32 * c)
{
    Header h = hi->h;
    int slot = hi->next_index;
    struct indexEntry * entry = NULL;;

    for (slot = hi->next_index; slot < h->indexUsed; slot++) {
        entry = h->index + slot;
        if (!ENTRY_IS_REGION(entry))
            break;
    }
    hi->next_index = slot;
    if (entry == NULL || slot >= h->indexUsed)
        return 0;
    hi->next_index++;

    if (tag)
        *tag = entry->info.tag;

    copyEntry(entry, type, p, c, 0);

    return 1;
}

static int indexCmp(const void *avp, const void *bvp)   /*@*/
{
    const struct indexEntry * ap = avp, * bp = bvp;
    return (ap->info.tag - bp->info.tag);
}

void headerSort(Header h)
{
    if (!h->sorted) {
        qsort(h->index, h->indexUsed, sizeof(*h->index), indexCmp);
        h->sorted = 1;
    }
}

static int offsetCmp(const void *avp, const void *bvp) /*@*/
{
    const struct indexEntry * ap = avp, * bp = bvp;
    int rc = (ap->info.offset - bp->info.offset);

    if (rc == 0)
        rc = (ap->info.tag - bp->info.tag);
    return rc;
}

void headerUnsort(Header h)
{
    qsort(h->index, h->indexUsed, sizeof(*h->index), offsetCmp);
}

Header headerCopy(Header h)
{
    Header nh = headerNew();
    HeaderIterator hi;
    int_32 tag, type, count;
    const void *ptr;
   
    for (hi = headerInitIterator(h);
        headerNextIterator(hi, &tag, &type, &ptr, &count);
        ptr = headerFreeData((void *)ptr, type))
    {
        headerAddEntry(nh, tag, type, ptr, count);
    }
    headerFreeIterator(hi);

    return headerReload(nh, HEADER_IMAGE);
}

Header headerLoad(void *uh)
{
    int_32 *ei = (int_32 *) uh;
    int_32 il = ntohl(ei[0]);           /* index length */
    int_32 dl = ntohl(ei[1]);           /* data length */
    int pvlen = sizeof(il) + sizeof(dl) +
               (il * sizeof(struct entryInfo)) + dl;
#ifdef  REMALLOC_HEADER_REGION
    void * pv = memcpy(xmalloc(pvlen), uh, pvlen);
#else
    void * pv = uh;
#endif
    Header h = xcalloc(1, sizeof(*h));
    struct entryInfo * pe;
    char * dataStart;
    struct indexEntry * entry; 
    int rdlen;
    int i;

    ei = (int_32 *) pv;
    pe = (struct entryInfo *) &ei[2];
    dataStart = (char *) (pe + il);

    h->indexAlloced = il + 1;
    h->indexUsed = il;
    h->index = xcalloc(h->indexAlloced, sizeof(*h->index));
    h->sorted = 1;
#ifdef  REMALLOC_HEADER_REGION
    h->region_allocated = 1;
#else
    h->region_allocated = 0;
#endif
    h->nrefs = 1;

    /*
     * XXX XFree86-libs, ash, and pdksh from Red Hat 5.2 have bogus
     * %verifyscript tag that needs to be diddled.
     */
    if (ntohl(pe->tag) == 15 &&
        ntohl(pe->type) == RPM_STRING_TYPE &&
        ntohl(pe->count) == 1)
    {
        pe->tag = htonl(1079);
    }

    entry = h->index;
    i = 0;
    if (!(htonl(pe->tag) < HEADER_I18NTABLE)) {
        h->legacy = 1;
        entry->info.type = REGION_TAG_TYPE;
        entry->info.tag = HEADER_IMAGE;
        entry->info.count = REGION_TAG_COUNT;
        entry->info.offset = ((char *)pe - dataStart); /* negative offset */

        entry->data = pe;
        entry->length = pvlen - sizeof(il) - sizeof(dl);
        rdlen = regionSwab(entry+1, il, 0, pe, dataStart, entry->info.offset);
        entry->rdlen = rdlen;
assert(rdlen == dl);

        entry++;
        h->indexUsed++;
    } else {
        int nb = ntohl(pe->count);
        int_32 rdl;
        int_32 ril;

        h->legacy = 0;
        entry->info.type = htonl(pe->type);
        if (entry->info.type < RPM_MIN_TYPE || entry->info.type > RPM_MAX_TYPE)
            return NULL;
        entry->info.count = htonl(pe->count);

        {  int off = ntohl(pe->offset);
           if (off) {
                int_32 * stei = memcpy(alloca(nb), dataStart + off, nb);
                rdl = -ntohl(stei[2]);  /* negative offset */
                ril = rdl/sizeof(*pe);
                entry->info.tag = htonl(pe->tag);
            } else {
                ril = il;
                rdl = (ril * sizeof(struct entryInfo));
                entry->info.tag = HEADER_IMAGE;
            }
        }
        entry->info.offset = -rdl;      /* negative offset */

        entry->data = pe;
        entry->length = pvlen - sizeof(il) - sizeof(dl);
        rdlen = regionSwab(entry+1, ril-1, 0, pe+1, dataStart, entry->info.offset);
        entry->rdlen = rdlen;

        if (ril < h->indexUsed) {
            struct indexEntry * newEntry = entry + ril;
            int ne = (h->indexUsed - ril);
            int rid = entry->info.offset+1;

            /* Load dribble entries from region. */
            rdlen += regionSwab(newEntry, ne, 0, pe+ril, dataStart, rid);

          { struct indexEntry * firstEntry = newEntry;
            int save = h->indexUsed;
            int j;

            /* Dribble entries replace duplicate region entries. */
            h->indexUsed -= ne;
            for (j = 0; j < ne; j++, newEntry++) {
                headerRemoveEntry(h, newEntry->info.tag);
                if (newEntry->info.tag == HEADER_BASENAMES)
                    headerRemoveEntry(h, HEADER_OLDFILENAMES);
            }

            /* If any duplicate entries were replaced, move new entries down. */
            if (h->indexUsed < (save - ne)) {
                memmove(h->index + h->indexUsed, firstEntry,
                        (ne * sizeof(*entry)));
            }
            h->indexUsed += ne;
          }
        }
    }

    h->sorted = 0;
    headerSort(h);

    return h;
}

Header headerCopyLoad(void *uh)
{
    int_32 *ei = (int_32 *) uh;
    int_32 il = ntohl(ei[0]);           /* index length */
    int_32 dl = ntohl(ei[1]);           /* data length */
    int pvlen = sizeof(il) + sizeof(dl) +
               (il * sizeof(struct entryInfo)) + dl;
    void * nuh = memcpy(xmalloc(pvlen), uh, pvlen);
    Header h;

    h = headerLoad(nuh);
    if (h == NULL) {
        free(nuh);
        return h;
    }
    h->region_allocated = 1;
    return h;
}

#if 0
int headerDrips(const Header h)
{
    struct indexEntry * entry; 
    int i;

    for (i = 0, entry = h->index; i < h->indexUsed; i++, entry++) {
        if (ENTRY_IS_REGION(entry)) {
            int rid = entry->info.offset;

            for (; i < h->indexUsed && entry->info.offset <= rid+1; i++, entry++) {
                if (entry->info.offset <= rid)
                    continue;
            }
            i--;
            entry--;
            continue;
        }

        /* Ignore deleted drips. */
        if (entry->data == NULL || entry->length <= 0)
            continue;
    }
    return 0;
}
#endif

static /*@only@*/ void * doHeaderUnload(Header h, /*@out@*/ int * lengthPtr)
        /*@modifies h, *lengthPtr @*/
{
    int_32 * ei;
    struct entryInfo * pe;
    char * dataStart;
    char * te;
    unsigned pad;
    unsigned len;
    int_32 il = 0;
    int_32 dl = 0;
    struct indexEntry * entry; 
    int_32 type;
    int i;
    int drlen, ndribbles;
    int driplen, ndrips;
    int legacy = 0;

    /* Sort entries by (offset,tag). */
    headerUnsort(h);

    /* Compute (il,dl) for all tags, including those deleted in region. */
    pad = 0;
    drlen = ndribbles = driplen = ndrips = 0;
    for (i = 0, entry = h->index; i < h->indexUsed; i++, entry++) {
        if (ENTRY_IS_REGION(entry)) {
            int_32 rdl = -entry->info.offset;   /* negative offset */
            int_32 ril = rdl/sizeof(*pe);
            int rid = entry->info.offset;

            il += ril;
            dl += entry->rdlen + entry->info.count;
            /* XXX Legacy regions do not include the region tag and data. */
            if (i == 0 && h->legacy)
                il += 1;

            /* Skip rest of entries in region, but account for dribbles. */
            for (; i < h->indexUsed && entry->info.offset <= rid+1; i++, entry++) {
                if (entry->info.offset <= rid)
                    continue;

                /* Alignment */
                type = entry->info.type;
                if (typeSizes[type] > 1) {
                    unsigned diff;
                    diff = typeSizes[type] - (dl % typeSizes[type]);
                    if (diff != typeSizes[type]) {
                        drlen += diff;
                        pad += diff;
                        dl += diff;
                    }
                }

                ndribbles++;
                il++;
                drlen += entry->length;
                dl += entry->length;
            }
            i--;
            entry--;
            continue;
        }

        /* Ignore deleted drips. */
        if (entry->data == NULL || entry->length <= 0)
            continue;

        /* Alignment */
        type = entry->info.type;
        if (typeSizes[type] > 1) {
            unsigned diff;
            diff = typeSizes[type] - (dl % typeSizes[type]);
            if (diff != typeSizes[type]) {
                driplen += diff;
                pad += diff;
                dl += diff;
            } else
                diff = 0;
        }

        ndrips++;
        il++;
        driplen += entry->length;
        dl += entry->length;
    }
    len = sizeof(il) + sizeof(dl) + (il * sizeof(*pe)) + dl;

    ei = xmalloc(len);
    ei[0] = htonl(il);
    ei[1] = htonl(dl);

    pe = (struct entryInfo *) &ei[2];
    dataStart = te = (char *) (pe + il);

    pad = 0;
    for (i = 0, entry = h->index; i < h->indexUsed; i++, entry++) {
        const char * src;
char *t;
        int count;
        int rdlen;

        if (entry->data == NULL || entry->length <= 0)
            continue;

t = te;
        pe->tag = htonl(entry->info.tag);
        pe->type = htonl(entry->info.type);
        pe->count = htonl(entry->info.count);

        if (ENTRY_IS_REGION(entry)) {
            int_32 rdl = -entry->info.offset;   /* negative offset */
            int_32 ril = rdl/sizeof(*pe) + ndribbles;
            int rid = entry->info.offset;

            src = (char *)entry->data;
            rdlen = entry->rdlen;

            /* XXX Legacy regions do not include the region tag and data. */
            if (i == 0 && h->legacy) {
                int_32 stei[4];

                legacy = 1;
                memcpy(pe+1, src, rdl);
                memcpy(te, src + rdl, rdlen);
                te += rdlen;

                pe->offset = htonl(te - dataStart);
                stei[0] = pe->tag;
                stei[1] = pe->type;
                stei[2] = htonl(-rdl-entry->info.count);
                stei[3] = pe->count;
                memcpy(te, stei, entry->info.count);
                te += entry->info.count;
                ril++;
                rdlen += entry->info.count;

                count = regionSwab(NULL, ril, 0, pe, t, 0);
                assert(count == rdlen);

            } else {

                memcpy(pe+1, src + sizeof(*pe), ((ril-1) * sizeof(*pe)));
                memcpy(te, src + (ril * sizeof(*pe)), rdlen+entry->info.count+drlen);
                te += rdlen;
                {   struct entryInfo * se = (struct entryInfo *)src;
                    int off = ntohl(se->offset);
                    pe->offset = (off) ? htonl(te - dataStart) : htonl(off);
                }
                te += entry->info.count + drlen;

                count = regionSwab(NULL, ril, 0, pe, t, 0);
                assert(count == rdlen+entry->info.count+drlen);
            }

            /* Skip rest of entries in region. */
            while (i < h->indexUsed && entry->info.offset <= rid+1) {
                i++;
                entry++;
            }
            i--;
            entry--;
            pe += ril;
            continue;
        }

        /* Ignore deleted drips. */
        if (entry->data == NULL || entry->length <= 0)
            continue;

        /* Alignment */
        type = entry->info.type;
        if (typeSizes[type] > 1) {
            unsigned diff;
            diff = typeSizes[type] - ((te - dataStart) % typeSizes[type]);
            if (diff != typeSizes[type]) {
                memset(te, 0, diff);
                te += diff;
                pad += diff;
            }
        }

        pe->offset = htonl(te - dataStart);

        /* copy data w/ endian conversions */
        switch (entry->info.type) {
        case RPM_INT32_TYPE:
            count = entry->info.count;
            src = entry->data;
            while (count--) {
                *((int_32 *)te) = htonl(*((int_32 *)src));
                te += sizeof(int_32);
                src += sizeof(int_32);
            }
            break;

        case RPM_INT16_TYPE:
            count = entry->info.count;
            src = entry->data;
            while (count--) {
                *((int_16 *)te) = htons(*((int_16 *)src));
                te += sizeof(int_16);
                src += sizeof(int_16);
            }
            break;

        default:
            memcpy(te, entry->data, entry->length);
            te += entry->length;
            break;
        }
        pe++;
    }
   
    /* Insure that there are no memcpy underruns/overruns. */
    assert(((char *)pe) == dataStart);
    assert((((char *)ei)+len) == te);

    if (lengthPtr)
        *lengthPtr = len;

    h->sorted = 0;
    headerSort(h);

    return (void *)ei;
}

void *headerUnload(Header h)
{
    int length;
    void * uh = doHeaderUnload(h, &length);
    return uh;
}

Header headerReload(Header h, int tag)
{
    Header nh;
    int length;
    void * uh = doHeaderUnload(h, &length);

    headerFree(h);
    nh = headerLoad(uh);
    if (nh == NULL) {
        free(uh);
        return nh;
    }
    if (nh->region_allocated)
        free(uh);
    nh->region_allocated = 1;
    if (ENTRY_IS_REGION(nh->index)) {
        if (tag == HEADER_SIGNATURES || tag == HEADER_IMMUTABLE)
            nh->index[0].info.tag = tag;
    }
    return nh;
}

int headerWrite(FD_t fd, Header h, enum hMagic magicp)
{
    ssize_t nb;
    int length;
    const void * uh;

    uh = doHeaderUnload(h, &length);
    switch (magicp) {
    case HEADER_MAGIC_YES:
        nb = Fwrite(header_magic, sizeof(char), sizeof(header_magic), fd);
        if (nb != sizeof(header_magic))
            goto exit;
        break;
    case HEADER_MAGIC_NO:
        break;
    }

    nb = Fwrite(uh, sizeof(char), length, fd);

exit:
    free((void *)uh);
    return (nb == length ? 0 : 1);
}

Header headerRead(FD_t fd, enum hMagic magicp)
{
    int_32 block[4];
    int_32 reserved;
    int_32 * ei = NULL;
    int_32 il;
    int_32 dl;
    int_32 magic;
    Header h = NULL;
    int len;
    int i;

    memset(block, 0, sizeof(block));
    i = 2;
    if (magicp == HEADER_MAGIC_YES)
        i += 2;

    if (timedRead(fd, (char *)block, i*sizeof(*block)) != (i * sizeof(*block)))
        goto exit;

    i = 0;

    if (magicp == HEADER_MAGIC_YES) {
        magic = block[i++];
        if (memcmp(&magic, header_magic, sizeof(magic)))
            goto exit;
        reserved = block[i++];
    }
    
    il = ntohl(block[i++]);
    dl = ntohl(block[i++]);

    len = sizeof(il) + sizeof(dl) + (il * sizeof(struct entryInfo)) + dl;

    /*
     * XXX Limit total size of header to 32Mb (~16 times largest known size).
     */
    if (len > (32*1024*1024))
        goto exit;

    ei = xmalloc(len);
    ei[0] = htonl(il);
    ei[1] = htonl(dl);
    len -= sizeof(il) + sizeof(dl);

    if (timedRead(fd, (char *)&ei[2], len) != len)
        goto exit;
    
    h = headerLoad(ei);

exit:
    if (h) {
        if (h->region_allocated)
            free(ei);
        h->region_allocated = 1;
    } else if (ei)
        free(ei);
    return h;
}

void headerDump(Header h, FILE *f, int flags, 
                const struct headerTagTableEntry * tags)
{
    int i;
    struct indexEntry *p;
    const struct headerTagTableEntry * tage;
    const char *tag;
    char *type;

    /* First write out the length of the index (count of index entries) */
    fprintf(f, "Entry count: %d\n", h->indexUsed);

    /* Now write the index */
    p = h->index;
    fprintf(f, "\n             CT  TAG                  TYPE         "
                "      OFSET      COUNT\n");
    for (i = 0; i < h->indexUsed; i++) {
        switch (p->info.type) {
        case RPM_NULL_TYPE:             type = "NULL_TYPE";     break;
        case RPM_CHAR_TYPE:             type = "CHAR_TYPE";     break;
        case RPM_BIN_TYPE:              type = "BIN_TYPE";      break;
        case RPM_INT8_TYPE:             type = "INT8_TYPE";     break;
        case RPM_INT16_TYPE:            type = "INT16_TYPE";    break;
        case RPM_INT32_TYPE:            type = "INT32_TYPE";    break;
        /*case RPM_INT64_TYPE:          type = "INT64_TYPE";    break;*/
        case RPM_STRING_TYPE:           type = "STRING_TYPE";   break;
        case RPM_STRING_ARRAY_TYPE:     type = "STRING_ARRAY_TYPE"; break;
        case RPM_I18NSTRING_TYPE:       type = "I18N_STRING_TYPE"; break;
        default:                        type = "(unknown)";     break;
        }

        tage = tags;
        while (tage->name && tage->val != p->info.tag) tage++;

        if (!tage->name)
            tag = "(unknown)";
        else
            tag = tage->name;

        fprintf(f, "Entry      : %.3d (%d)%-14s %-18s 0x%.8x %.8d\n", i,
                p->info.tag, tag, type, (unsigned) p->info.offset, (int) 
                p->info.count);

        if (flags & HEADER_DUMP_INLINE) {
            char *dp = p->data;
            int c = p->info.count;
            int ct = 0;

            /* Print the data inline */
            switch (p->info.type) {
            case RPM_INT32_TYPE:
                while (c--) {
                    fprintf(f, "       Data: %.3d 0x%08x (%d)\n", ct++,
                            (unsigned) *((int_32 *) dp),
                            (int) *((int_32 *) dp));
                    dp += sizeof(int_32);
                }
                break;

            case RPM_INT16_TYPE:
                while (c--) {
                    fprintf(f, "       Data: %.3d 0x%04x (%d)\n", ct++,
                            (unsigned) (*((int_16 *) dp) & 0xffff),
                            (int) *((int_16 *) dp));
                    dp += sizeof(int_16);
                }
                break;
            case RPM_INT8_TYPE:
                while (c--) {
                    fprintf(f, "       Data: %.3d 0x%02x (%d)\n", ct++,
                            (unsigned) (*((int_8 *) dp) & 0xff),
                            (int) *((int_8 *) dp));
                    dp += sizeof(int_8);
                }
                break;
            case RPM_BIN_TYPE:
                while (c > 0) {
                    fprintf(f, "       Data: %.3d ", ct);
                    while (c--) {
                        fprintf(f, "%02x ", (unsigned) (*(int_8 *)dp & 0xff));
                        ct++;
                        dp += sizeof(int_8);
                        if (! (ct % 8)) {
                            break;
                        }
                    }
                    fprintf(f, "\n");
                }
                break;
            case RPM_CHAR_TYPE:
                while (c--) {
                    char ch = (char) *((char *) dp);
                    fprintf(f, "       Data: %.3d 0x%2x %c (%d)\n", ct++,
                            (unsigned)(ch & 0xff),
                            (isprint(ch) ? ch : ' '),
                            (int) *((char *) dp));
                    dp += sizeof(char);
                }
                break;
            case RPM_STRING_TYPE:
            case RPM_STRING_ARRAY_TYPE:
            case RPM_I18NSTRING_TYPE:
                while (c--) {
                    fprintf(f, "       Data: %.3d %s\n", ct++, (char *) dp);
                    dp = strchr(dp, 0);
                    dp++;
                }
                break;
            default:
                fprintf(stderr, _("Data type %d not supported\n"), 
                        (int) p->info.type);
                exit(EXIT_FAILURE);
                /*@notreached@*/ break;
            }
        }
        p++;
    }
}

static struct indexEntry *findEntry(Header h, int_32 tag, int_32 type)
{
    struct indexEntry * entry, * entry2, * last;
    struct indexEntry key;

    if (!h->sorted) headerSort(h);

    key.info.tag = tag;

    entry2 = entry = 
        bsearch(&key, h->index, h->indexUsed, sizeof(*h->index), indexCmp);
    if (entry == NULL)
        return NULL;

    if (type == RPM_NULL_TYPE)
        return entry;

    /* look backwards */
    while (entry->info.tag == tag && entry->info.type != type &&
           entry > h->index) entry--;

    if (entry->info.tag == tag && entry->info.type == type)
        return entry;

    last = h->index + h->indexUsed;
    while (entry2->info.tag == tag && entry2->info.type != type &&
           entry2 < last) entry2++;

    if (entry->info.tag == tag && entry->info.type == type)
        return entry;

    return NULL;
}

int headerIsEntry(Header h, int_32 tag)
{
    return (findEntry(h, tag, RPM_NULL_TYPE) ? 1 : 0);
}

int headerGetRawEntry(Header h, int_32 tag, int_32 * type, const void ** p,
                        int_32 *c)
{
    struct indexEntry * entry;

    if (p == NULL) return headerIsEntry(h, tag);

    /* First find the tag */
    entry = findEntry(h, tag, RPM_NULL_TYPE);
    if (!entry) {
        if (p) *p = NULL;
        if (c) *c = 0;
        return 0;
    }

    copyEntry(entry, type, p, c, 0);

    return 1;
}

static int headerMatchLocale(const char *td, const char *l, const char *le)
        /*@*/
{
    const char *fe;


#if 0
  { const char *s, *ll, *CC, *EE, *dd;
    char *lbuf, *t.

    /* Copy the buffer and parse out components on the fly. */
    lbuf = alloca(le - l + 1);
    for (s = l, ll = t = lbuf; *s; s++, t++) {
        switch (*s) {
        case '_':
            *t = '\0';
            CC = t + 1;
            break;
        case '.':
            *t = '\0';
            EE = t + 1;
            break;
        case '@':
            *t = '\0';
            dd = t + 1;
            break;
        default:
            *t = *s;
            break;
        }
    }

    if (ll)     /* ISO language should be lower case */
        for (t = ll; *t; t++)   *t = tolower(*t);
    if (CC)     /* ISO country code should be upper case */
        for (t = CC; *t; t++)   *t = toupper(*t);

    /* There are a total of 16 cases to attempt to match. */
  }
#endif

    /* First try a complete match. */
    if (strlen(td) == (le-l) && !strncmp(td, l, (le - l)))
        return 1;

    /* Next, try stripping optional dialect and matching.  */
    for (fe = l; fe < le && *fe != '@'; fe++)
        ;
    if (fe < le && !strncmp(td, l, (fe - l)))
        return 1;

    /* Next, try stripping optional codeset and matching.  */
    for (fe = l; fe < le && *fe != '.'; fe++)
        ;
    if (fe < le && !strncmp(td, l, (fe - l)))
        return 1;

    /* Finally, try stripping optional country code and matching. */
    for (fe = l; fe < le && *fe != '_'; fe++)
        ;
    if (fe < le && !strncmp(td, l, (fe - l)))
        return 1;

    return 0;
}

/*@dependent@*/ static char *
headerFindI18NString(Header h, struct indexEntry *entry)
{
    const char *lang, *l, *le;
    struct indexEntry * table;

    /* XXX Drepper sez' this is the order. */
    if ((lang = getenv("LANGUAGE")) == NULL &&
        (lang = getenv("LC_ALL")) == NULL &&
        (lang = getenv("LC_MESSAGES")) == NULL &&
        (lang = getenv("LANG")) == NULL)
            return entry->data;
    
    if ((table = findEntry(h, HEADER_I18NTABLE, RPM_STRING_ARRAY_TYPE)) == NULL)
        return entry->data;

    for (l = lang; *l; l = le) {
        const char *td;
        char *ed;
        int langNum;

        while (*l && *l == ':')                 /* skip leading colons */
            l++;
        if (*l == '\0')
            break;
        for (le = l; *le && *le != ':'; le++)   /* find end of this locale */
            ;

        /* For each entry in the header ... */
        for (langNum = 0, td = table->data, ed = entry->data;
             langNum < entry->info.count;
             langNum++, td += strlen(td) + 1, ed += strlen(ed) + 1) {

                if (headerMatchLocale(td, l, le))
                    return ed;

        }
    }

    return entry->data;
}

static int intGetEntry(Header h, int_32 tag, /*@out@*/ int_32 *type,
        /*@out@*/ const void **p, /*@out@*/ int_32 *c, int minMem)
                /*@modifies *type, *p, *c @*/
{
    struct indexEntry * entry;

    /* First find the tag */
    entry = findEntry(h, tag, RPM_NULL_TYPE);
    if (entry == NULL) {
        if (type) type = 0;
        if (p) *p = NULL;
        if (c) *c = 0;
        return 0;
    }

    switch (entry->info.type) {
    case RPM_I18NSTRING_TYPE:
        if (type) *type = RPM_STRING_TYPE;
        if (c) *c = 1;
        /*@-dependenttrans@*/
        if (p) *p = headerFindI18NString(h, entry);
        /*@=dependenttrans@*/
        break;
    default:
        copyEntry(entry, type, p, c, minMem);
        break;
    }

    return 1;
}

int headerGetEntryMinMemory(Header h, int_32 tag, int_32 *type, const void **p, 
                            int_32 *c)
{
    return intGetEntry(h, tag, type, p, c, 1);
}

int headerGetEntry(Header h, int_32 tag, int_32 * type, void **p, int_32 * c)
{
    return intGetEntry(h, tag, type, (const void **)p, c, 0);
}

Header headerNew()
{
    Header h = xcalloc(1, sizeof(*h));

    h->indexAlloced = INDEX_MALLOC_SIZE;
    h->indexUsed = 0;
    h->region_allocated = 0;
    h->sorted = 1;
    h->legacy = 0;
    h->nrefs = 1;

    h->index = (h->indexAlloced
        ? xcalloc(h->indexAlloced, sizeof(*h->index))
        : NULL);

    return h;
}

void headerFree(Header h)
{
    if (h == NULL || --h->nrefs > 0)
        return;

    if (h->index) {
        struct indexEntry * entry = h->index;
        int i;
        for (i = 0; i < h->indexUsed; i++, entry++) {
            if (h->region_allocated && ENTRY_IS_REGION(entry)) {
                if (entry->length > 0) {
                    int_32 * ei = entry->data;
                    ei -= 2; /* XXX HACK: adjust to beginning of header. */
                    free(ei);
                }
            } else if (!ENTRY_IN_REGION(entry)) {
                free(entry->data);
            }
            entry->data = NULL;
        }
        free(h->index);
        h->index = NULL;
    }

    /*@-refcounttrans@*/ free(h); /*@=refcounttrans@*/
}

Header headerLink(Header h)
{
    h->nrefs++;
    /*@-refcounttrans@*/ return h; /*@=refcounttrans@*/
}

int headerUsageCount(Header h)
{
    return h->nrefs;
}

unsigned int headerSizeof(Header h, enum hMagic magicp)
{
    struct indexEntry * entry;
    unsigned int size = 0, pad = 0;
    int i;

    headerSort(h);

    switch (magicp) {
    case HEADER_MAGIC_YES:
        size += sizeof(header_magic);
        break;
    case HEADER_MAGIC_NO:
        break;
    }

    size += 2 * sizeof(int_32); /* count of index entries */

    for (i = 0, entry = h->index; i < h->indexUsed; i++, entry++) {
        unsigned diff;
        int_32 type;

        /* Regions go in as is ... */
        if (ENTRY_IS_REGION(entry)) {
            size += entry->length;
            /* XXX Legacy regions do not include the region tag and data. */
            if (i == 0 && h->legacy)
                size += sizeof(struct entryInfo) + entry->info.count;
            continue;
        }

        /* ... and region elements are skipped. */
        if (entry->info.offset < 0)
            continue;

        /* Alignment */
        type = entry->info.type;
        if (typeSizes[type] > 1) {
            diff = typeSizes[type] - (size % typeSizes[type]);
            if (diff != typeSizes[type]) {
                size += diff;
                pad += diff;
            }
        }

        size += sizeof(struct entryInfo) + entry->length;
    }

    return size;
}

static void copyData(int_32 type, /*@out@*/ void * dstPtr, const void * srcPtr,
        int_32 c, int dataLength)
                /*@modifies *dstPtr @*/
{
    const char ** src;
    char * dst;
    int i, len;

    switch (type) {
    case RPM_STRING_ARRAY_TYPE:
    case RPM_I18NSTRING_TYPE:
        /* Otherwise, p is char** */
        i = c;
        src = (const char **) srcPtr;
        dst = dstPtr;
        while (i--) {
            len = *src ? strlen(*src) + 1 : 0;
            memcpy(dst, *src, len);
            dst += len;
            src++;
        }
        break;

    default:
        memcpy(dstPtr, srcPtr, dataLength);
        break;
    }
}

static void * grabData(int_32 type, const void * p, int_32 c,
        /*@out@*/ int * lengthPtr)
                /*@modifies *lengthPtr @*/
{
    int length = dataLength(type, p, c, 0);
    void * data = xmalloc(length);

    copyData(type, data, p, c, length);

    if (lengthPtr)
        *lengthPtr = length;
    return data;
}

int headerAddEntry(Header h, int_32 tag, int_32 type, const void *p, int_32 c)
{
    struct indexEntry *entry;

    if (c <= 0) {
        fprintf(stderr, _("Bad count for headerAddEntry(): %d\n"), (int) c);
        exit(EXIT_FAILURE);
        /*@notreached@*/
    }

    /* Allocate more index space if necessary */
    if (h->indexUsed == h->indexAlloced) {
        h->indexAlloced += INDEX_MALLOC_SIZE;
        h->index = xrealloc(h->index,
                        h->indexAlloced * sizeof(struct indexEntry));
    }

    /* Fill in the index */
    entry = h->index + h->indexUsed;
    entry->info.tag = tag;
    entry->info.type = type;
    entry->info.count = c;
    entry->info.offset = 0;
    entry->data = grabData(type, p, c, &entry->length);

    if (h->indexUsed > 0 && tag < h->index[h->indexUsed-1].info.tag)
        h->sorted = 0;
    h->indexUsed++;

    return 1;
}

char **
headerGetLangs(Header h)
{
    char **s, *e, **table;
    int i, type, count;

    if (!headerGetRawEntry(h, HEADER_I18NTABLE, &type, (const void **)&s, &count))
        return NULL;

    if ((table = (char **)xcalloc((count+1), sizeof(char *))) == NULL)
        return NULL;

    for (i = 0, e = *s; i < count > 0; i++, e += strlen(e)+1)
        table[i] = e;
    table[count] = NULL;

    return table;
}

int headerAddI18NString(Header h, int_32 tag, const char * string, const char * lang)
{
    struct indexEntry * table, * entry;
    char * chptr;
    const char ** strArray;
    int length;
    int ghosts;
    int i, langNum;
    char * buf;

    table = findEntry(h, HEADER_I18NTABLE, RPM_STRING_ARRAY_TYPE);
    entry = findEntry(h, tag, RPM_I18NSTRING_TYPE);

    if (!table && entry)
        return 0;               /* this shouldn't ever happen!! */

    if (!table && !entry) {
        const char * charArray[2];
        int count = 0;
        if (!lang || (lang[0] == 'C' && lang[1] == '\0')) {
            /*@-observertrans@*/
            charArray[count++] = "C";
            /*@=observertrans@*/
        } else {
            /*@-observertrans@*/
            charArray[count++] = "C";
            /*@=observertrans@*/
            charArray[count++] = lang;
        }
        if (!headerAddEntry(h, HEADER_I18NTABLE, RPM_STRING_ARRAY_TYPE, 
                        &charArray, count))
            return 0;
        table = findEntry(h, HEADER_I18NTABLE, RPM_STRING_ARRAY_TYPE);
    }

    if (!lang) lang = "C";

    chptr = table->data;
    for (langNum = 0; langNum < table->info.count; langNum++) {
        if (!strcmp(chptr, lang)) break;
        chptr += strlen(chptr) + 1;
    }

    if (langNum >= table->info.count) {
        length = strlen(lang) + 1;
        if (ENTRY_IN_REGION(table)) {
            char * t = xmalloc(table->length + length);
            memcpy(t, table->data, table->length);
            table->data = t;
            table->info.offset = 0;
        } else
            table->data = xrealloc(table->data, table->length + length);
        memcpy(((char *)table->data) + table->length, lang, length);
        table->length += length;
        table->info.count++;
    }

    if (!entry) {
        strArray = alloca(sizeof(*strArray) * (langNum + 1));
        for (i = 0; i < langNum; i++)
            strArray[i] = "";
        strArray[langNum] = string;
        return headerAddEntry(h, tag, RPM_I18NSTRING_TYPE, strArray, 
                                langNum + 1);
    } else if (langNum >= entry->info.count) {
        ghosts = langNum - entry->info.count;
        
        length = strlen(string) + 1 + ghosts;
        if (ENTRY_IN_REGION(entry)) {
            char * t = xmalloc(entry->length + length);
            memcpy(t, entry->data, entry->length);
            entry->data = t;
            entry->info.offset = 0;
        } else
            entry->data = xrealloc(entry->data, entry->length + length);

        memset(((char *)entry->data) + entry->length, '\0', ghosts);
        strcpy(((char *)entry->data) + entry->length + ghosts, string);

        entry->length += length;
        entry->info.count = langNum + 1;
    } else {
        char *b, *be, *e, *ee, *t;
        size_t bn, sn, en;

        /* Set beginning/end pointers to previous data */
        b = be = e = ee = entry->data;
        for (i = 0; i < table->info.count; i++) {
            if (i == langNum)
                be = ee;
            ee += strlen(ee) + 1;
            if (i == langNum)
                e  = ee;
        }

        /* Get storage for new buffer */
        bn = (be-b);
        sn = strlen(string) + 1;
        en = (ee-e);
        length = bn + sn + en;
        t = buf = xmalloc(length);

        /* Copy values into new storage */
        memcpy(t, b, bn);
        t += bn;
        memcpy(t, string, sn);
        t += sn;
        memcpy(t, e, en);
        t += en;

        /* Replace I18N string array */
        entry->length -= strlen(be) + 1;
        entry->length += sn;
        
        if (ENTRY_IN_REGION(entry)) {
            entry->info.offset = 0;
        } else
            free(entry->data);
        entry->data = buf;
    }

    return 0;
}

/* if there are multiple entries with this tag, the first one gets replaced */
int headerModifyEntry(Header h, int_32 tag, int_32 type, void *p, int_32 c)
{
    struct indexEntry *entry;
    void * oldData;

    /* First find the tag */
    entry = findEntry(h, tag, type);
    if (!entry)
        return 0;

    /* make sure entry points to the first occurence of this tag */
    while (entry > h->index && (entry - 1)->info.tag == tag)  
        entry--;

    /* free after we've grabbed the new data in case the two are intertwined;
       that's a bad idea but at least we won't break */
    oldData = entry->data;

    entry->info.count = c;
    entry->info.type = type;
    entry->data = grabData(type, p, c, &entry->length);

    if (ENTRY_IN_REGION(entry)) {
        entry->info.offset = 0;
    } else
        free(oldData);

    return 1;
}

int headerAddOrAppendEntry(Header h, int_32 tag, int_32 type,
                           void * p, int_32 c)
{
    return (findEntry(h, tag, type)
        ? headerAppendEntry(h, tag, type, p, c)
        : headerAddEntry(h, tag, type, p, c));
}

int headerAppendEntry(Header h, int_32 tag, int_32 type, void * p, int_32 c)
{
    struct indexEntry *entry;
    int length;

    /* First find the tag */
    entry = findEntry(h, tag, type);
    if (!entry)
        return 0;

    if (type == RPM_STRING_TYPE || type == RPM_I18NSTRING_TYPE) {
        /* we can't do this */
        return 0;
    }

    length = dataLength(type, p, c, 0);

    if (ENTRY_IN_REGION(entry)) {
        char * t = xmalloc(entry->length + length);
        memcpy(t, entry->data, entry->length);
        entry->data = t;
        entry->info.offset = 0;
    } else
        entry->data = xrealloc(entry->data, entry->length + length);

    copyData(type, ((char *) entry->data) + entry->length, p, c, length);

    entry->length += length;

    entry->info.count += c;

    return 1;
}

int headerRemoveEntry(Header h, int_32 tag)
{
    struct indexEntry * last = h->index + h->indexUsed;
    struct indexEntry * entry, * first;
    int ne;

    entry = findEntry(h, tag, RPM_NULL_TYPE);
    if (!entry) return 1;

    /* Make sure entry points to the first occurence of this tag. */
    while (entry > h->index && (entry - 1)->info.tag == tag)  
        entry--;

    /* Free data for tags being removed. */
    for (first = entry; first < last; first++) {
        void * data;
        if (first->info.tag != tag)
            break;
        data = first->data;
        first->data = NULL;
        first->length = 0;
        if (ENTRY_IN_REGION(first))
            continue;
        free(data);
    }

    ne = (first - entry);
    if (ne > 0) {
        h->indexUsed -= ne;
        ne = last - first;
        if (ne > 0)
            memmove(entry, first, (ne * sizeof(*entry)));
    }

    return 0;
}

static char escapedChar(const char ch)  /*@*/
{
    switch (ch) {
    case 'a':   return '\a';
    case 'b':   return '\b';
    case 'f':   return '\f';
    case 'n':   return '\n';
    case 'r':   return '\r';
    case 't':   return '\t';
    case 'v':   return '\v';
    default:    return ch;
    }
}

static void freeFormat( /*@only@*/ struct sprintfToken * format, int num)
{
    int i;

    for (i = 0; i < num; i++) {
        switch (format[i].type) {
        case PTOK_ARRAY:
            freeFormat(format[i].u.array.format, format[i].u.array.numTokens);
            break;
        case PTOK_COND:
            freeFormat(format[i].u.cond.ifFormat, 
                        format[i].u.cond.numIfTokens);
            freeFormat(format[i].u.cond.elseFormat, 
                        format[i].u.cond.numElseTokens);
            break;
        case PTOK_NONE:
        case PTOK_TAG:
        case PTOK_STRING:
        default:
            break;
        }
    }
    free(format);
}

static void findTag(char * name, const struct headerTagTableEntry * tags, 
                    const struct headerSprintfExtension * extensions,
                    /*@out@*/const struct headerTagTableEntry ** tagMatch,
                    /*@out@*/const struct headerSprintfExtension ** extMatch)
        /*@modifies *tagMatch, *extMatch @*/
{
    const struct headerTagTableEntry * entry;
    const struct headerSprintfExtension * ext;
    const char * tagname;

    *tagMatch = NULL;
    *extMatch = NULL;

    if (strncmp("RPMTAG_", name, sizeof("RPMTAG_")-1)) {
        char * t = alloca(strlen(name) + sizeof("RPMTAG_"));
        (void) stpcpy( stpcpy(t, "RPMTAG_"), name);
        tagname = t;
    } else {
        tagname = name;
    }

    /* Search extensions first to permit overriding header tags. */
    ext = extensions;
    while (ext->type != HEADER_EXT_LAST) {
        if (ext->type == HEADER_EXT_TAG && !strcasecmp(ext->name, tagname))
            break;

        if (ext->type == HEADER_EXT_MORE)
            ext = ext->u.more;
        else
            ext++;
    }

    if (ext->type == HEADER_EXT_TAG) {
        *extMatch = ext;
        return;
    }

    /* Search header tags. */
    for (entry = tags; entry->name; entry++)
        if (!strcasecmp(entry->name, tagname)) break;

    if (entry->name) {
        *tagMatch = entry;
        return;
    }
}

/* forward ref */
static int parseExpression(struct sprintfToken * token, char * str, 
        const struct headerTagTableEntry * tags, 
        const struct headerSprintfExtension * extensions,
        /*@out@*/char ** endPtr, /*@out@*/const char ** errmsg)
                /*@modifies str, *str, *token, *endPtr, *errmsg @*/;

static int parseFormat(char * str, const struct headerTagTableEntry * tags,
        const struct headerSprintfExtension * extensions,
        /*@out@*/struct sprintfToken ** formatPtr, /*@out@*/int * numTokensPtr,
        /*@out@*/char ** endPtr, int state, /*@out@*/const char ** errmsg)
          /*@modifies str, *str, *formatPtr, *numTokensPtr, *endPtr, *errmsg @*/
{
    char * chptr, * start, * next, * dst;
    struct sprintfToken * format;
    int numTokens;
    int currToken;
    const struct headerTagTableEntry * tag;
    const struct headerSprintfExtension * ext;
    int i;
    int done = 0;

    /* upper limit on number of individual formats */
    numTokens = 0;
    for (chptr = str; *chptr; chptr++)
        if (*chptr == '%') numTokens++;
    numTokens = numTokens * 2 + 1;

    format = xcalloc(numTokens, sizeof(*format));
    if (endPtr) *endPtr = NULL;

    /*@-infloops@*/
    dst = start = str;
    currToken = -1;
    while (*start) {
        switch (*start) {
        case '%':
            /* handle %% */
            if (*(start + 1) == '%') {
                if (currToken < 0 || format[currToken].type != PTOK_STRING) {
                    currToken++;
                    format[currToken].type = PTOK_STRING;
                    dst = format[currToken].u.string.string = start;
                }

                start++;

                *dst++ = *start++;

                break; /* out of switch */
            } 

            currToken++;
            *dst++ = '\0';
            start++;

            if (*start == '|') {
                char * newEnd;

                start++;
                if (parseExpression(format + currToken, start, tags, 
                                    extensions, &newEnd, errmsg)) {
                    freeFormat(format, numTokens);
                    return 1;
                }
                start = newEnd;
                break; /* out of switch */
            }

            format[currToken].u.tag.format = start;
            format[currToken].u.tag.pad = 0;
            format[currToken].u.tag.justOne = 0;
            format[currToken].u.tag.arrayCount = 0;

            chptr = start;
            while (*chptr && *chptr != '{' && *chptr != '%') chptr++;
            if (!*chptr || *chptr == '%') {
                /*@-observertrans@*/
                *errmsg = _("missing { after %");
                /*@=observertrans@*/
                freeFormat(format, numTokens);
                return 1;
            }

            *chptr++ = '\0';

            while (start < chptr) {
                if (isdigit(*start)) {
                    i = strtoul(start, &start, 10);
                    format[currToken].u.tag.pad += i;
                } else {
                    start++;
                }
            }

            if (*start == '=') {
                format[currToken].u.tag.justOne = 1;
                start++;
            } else if (*start == '#') {
                format[currToken].u.tag.justOne = 1;
                format[currToken].u.tag.arrayCount = 1;
                start++;
            }

            next = start;
            while (*next && *next != '}') next++;
            if (!*next) {
                /*@-observertrans@*/
                *errmsg = _("missing } after %{");
                /*@=observertrans@*/
                freeFormat(format, numTokens);
                return 1;
            }
            *next++ = '\0';

            chptr = start;
            while (*chptr && *chptr != ':') chptr++;

            if (*chptr) {
                *chptr++ = '\0';
                if (!*chptr) {
                    /*@-observertrans@*/
                    *errmsg = _("empty tag format");
                    /*@=observertrans@*/
                    freeFormat(format, numTokens);
                    return 1;
                }
                format[currToken].u.tag.type = chptr;
            } else {
                format[currToken].u.tag.type = NULL;
            }
            
            if (!*start) {
                /*@-observertrans@*/
                *errmsg = _("empty tag name");
                /*@=observertrans@*/
                freeFormat(format, numTokens);
                return 1;
            }

            i = 0;
            findTag(start, tags, extensions, &tag, &ext);

            if (tag) {
                format[currToken].u.tag.ext = NULL;
                format[currToken].u.tag.tag = tag->val;
            } else if (ext) {
                format[currToken].u.tag.ext = ext->u.tagFunction;
                format[currToken].u.tag.extNum = ext - extensions;
            } else {
                /*@-observertrans@*/
                *errmsg = _("unknown tag");
                /*@=observertrans@*/
                freeFormat(format, numTokens);
                return 1;
            }

            format[currToken].type = PTOK_TAG;

            start = next;

            break;

        case '[':
            *dst++ = '\0';
            *start++ = '\0';
            currToken++;

            if (parseFormat(start, tags, extensions, 
                            &format[currToken].u.array.format,
                            &format[currToken].u.array.numTokens,
                            &start, PARSER_IN_ARRAY, errmsg)) {
                freeFormat(format, numTokens);
                return 1;
            }

            if (!start) {
                /*@-observertrans@*/
                *errmsg = _("] expected at end of array");
                /*@=observertrans@*/
                freeFormat(format, numTokens);
                return 1;
            }

            dst = start;

            format[currToken].type = PTOK_ARRAY;

            break;

        case ']':
        case '}':
            if ((*start == ']' && state != PARSER_IN_ARRAY) ||
                (*start == '}' && state != PARSER_IN_EXPR)) {
                if (*start == ']')
                    /*@-observertrans@*/
                    *errmsg = _("unexpected ]");
                    /*@=observertrans@*/
                else
                    /*@-observertrans@*/
                    *errmsg = _("unexpected }");
                    /*@=observertrans@*/
                freeFormat(format, numTokens);
                return 1;
            }
            *start++ = '\0';
            *endPtr = start;
            done = 1;
            break;

        default:
            if (currToken < 0 || format[currToken].type != PTOK_STRING) {
                currToken++;
                format[currToken].type = PTOK_STRING;
                dst = format[currToken].u.string.string = start;
            }

            if (*start == '\\') {
                start++;
                *dst++ = escapedChar(*start++);
            } else {
                *dst++ = *start++;
            }
            break;
        }
        if (done)
            break;
    }
    /*@=infloops@*/

    *dst = '\0';

    currToken++;
    for (i = 0; i < currToken; i++) {
        if (format[i].type == PTOK_STRING)
            format[i].u.string.len = strlen(format[i].u.string.string);
    }

    *numTokensPtr = currToken;
    *formatPtr = format;

    return 0;
}

static int parseExpression(struct sprintfToken * token, char * str, 
        const struct headerTagTableEntry * tags, 
        const struct headerSprintfExtension * extensions,
        /*@out@*/ char ** endPtr, /*@out@*/ const char ** errmsg)
{
    const struct headerTagTableEntry * tag;
    const struct headerSprintfExtension * ext;
    char * chptr;
    char * end;

    *errmsg = NULL;
    chptr = str;
    while (*chptr && *chptr != '?') chptr++;

    if (*chptr != '?') {
        /*@-observertrans@*/
        *errmsg = _("? expected in expression");
        /*@=observertrans@*/
        return 1;
    }

    *chptr++ = '\0';;

    if (*chptr != '{') {
        /*@-observertrans@*/
        *errmsg = _("{ expected after ? in expression");
        /*@=observertrans@*/
        return 1;
    }

    chptr++;

    if (parseFormat(chptr, tags, extensions, &token->u.cond.ifFormat, 
                    &token->u.cond.numIfTokens, &end, PARSER_IN_EXPR, errmsg)) 
        return 1;

    if (!*end) {
        /*@-observertrans@*/
        *errmsg = _("} expected in expression");
        /*@=observertrans@*/
        freeFormat(token->u.cond.ifFormat, token->u.cond.numIfTokens);
        token->u.cond.ifFormat = NULL;
        return 1;
    }

    chptr = end;
    if (*chptr != ':' && *chptr != '|') {
        /*@-observertrans@*/
        *errmsg = _(": expected following ? subexpression");
        /*@=observertrans@*/
        freeFormat(token->u.cond.ifFormat, token->u.cond.numIfTokens);
        token->u.cond.ifFormat = NULL;
        return 1;
    }

    if (*chptr == '|') {
        parseFormat(xstrdup(""), tags, extensions, &token->u.cond.elseFormat, 
                        &token->u.cond.numElseTokens, &end, PARSER_IN_EXPR, 
                        errmsg);
    } else {
        chptr++;

        if (*chptr != '{') {
            /*@-observertrans@*/
            *errmsg = _("{ expected after : in expression");
            /*@=observertrans@*/
            freeFormat(token->u.cond.ifFormat, token->u.cond.numIfTokens);
            token->u.cond.ifFormat = NULL;
            return 1;
        }

        chptr++;

        if (parseFormat(chptr, tags, extensions, &token->u.cond.elseFormat, 
                        &token->u.cond.numElseTokens, &end, PARSER_IN_EXPR, 
                        errmsg)) 
            return 1;
        if (!*end) {
            /*@-observertrans@*/
            *errmsg = _("} expected in expression");
            /*@=observertrans@*/
            freeFormat(token->u.cond.ifFormat, token->u.cond.numIfTokens);
            token->u.cond.ifFormat = NULL;
            return 1;
        }

        chptr = end;
        if (*chptr != '|') {
            /*@-observertrans@*/
            *errmsg = _("| expected at end of expression");
            /*@=observertrans@*/
            freeFormat(token->u.cond.ifFormat, token->u.cond.numIfTokens);
            token->u.cond.ifFormat = NULL;
            freeFormat(token->u.cond.elseFormat, token->u.cond.numElseTokens);
            token->u.cond.elseFormat = NULL;
            return 1;
        }
    }
        
    chptr++;

    *endPtr = chptr;

    findTag(str, tags, extensions, &tag, &ext);

    if (tag) {
        token->u.cond.tag.ext = NULL;
        token->u.cond.tag.tag = tag->val;
    } else if (ext) {
        token->u.cond.tag.ext = ext->u.tagFunction;
        token->u.cond.tag.extNum = ext - extensions;
    } else {
        token->u.cond.tag.ext = NULL;
        token->u.cond.tag.tag = -1;
    }
        
    token->type = PTOK_COND;

    return 0;
}

static int getExtension(Header h, headerTagTagFunction fn,
        /*@out@*/ int_32 * typeptr, /*@out@*/ const void ** data,
        /*@out@*/ int_32 * countptr, struct extensionCache * ext)
                /*@modifies *typeptr, *data, *countptr, ext->avail @*/
{
    if (!ext->avail) {
        if (fn(h, &ext->type, &ext->data, &ext->count, &ext->freeit))
            return 1;
        ext->avail = 1;
    }

    *typeptr = ext->type;
    *data = ext->data;
    *countptr = ext->count;

    return 0;
}

static char * formatValue(struct sprintfTag * tag, Header h, 
                          const struct headerSprintfExtension * extensions,
                          struct extensionCache * extCache, int element)
                /*@modifies h, extCache->avail @*/
{
    int len;
    char buf[20];
    int_32 count, type;
    const void * data;
    unsigned int intVal;
    char * val = NULL;
    const char ** strarray;
    int mayfree = 0;
    int countBuf;
    headerTagFormatFunction tagtype = NULL;
    const struct headerSprintfExtension * ext;

    if (tag->ext) {
        if (getExtension(h, tag->ext, &type, &data, &count, 
                         extCache + tag->extNum)) {
            count = 1;
            type = RPM_STRING_TYPE;     
            data = "(none)";            /* XXX i18n? NO!, sez; gafton */
        }
    } else {
        if (!headerGetEntry(h, tag->tag, &type, (void **)&data, &count)){
            count = 1;
            type = RPM_STRING_TYPE;     
            data = "(none)";            /* XXX i18n? NO!, sez; gafton */
        }

        mayfree = 1;
    }

    if (tag->arrayCount) {
        /*@-observertrans -modobserver@*/
        data = headerFreeData(data, type);
        /*@=observertrans =modobserver@*/

        countBuf = count;
        data = &countBuf;
        count = 1;
        type = RPM_INT32_TYPE;
    }

    (void) stpcpy( stpcpy(buf, "%"), tag->format);

    if (tag->type) {
        ext = extensions;
        while (ext->type != HEADER_EXT_LAST) {
            if (ext->type == HEADER_EXT_FORMAT && 
                !strcmp(ext->name, tag->type)) {
                tagtype = ext->u.formatFunction;
                break;
            }

            if (ext->type == HEADER_EXT_MORE)
                ext = ext->u.more;
            else
                ext++;
        }
    }
    
    switch (type) {
    case RPM_STRING_ARRAY_TYPE:
        strarray = (const char **)data;

        if (tagtype)
            val = tagtype(RPM_STRING_TYPE, strarray[element], buf, tag->pad, 0);

        if (!val) {
            strcat(buf, "s");

            len = strlen(strarray[element]) + tag->pad + 20;
            val = xmalloc(len);
            sprintf(val, buf, strarray[element]);
        }

        /*@-observertrans -modobserver@*/
        if (mayfree) free((void *)data);
        /*@=observertrans =modobserver@*/

        break;

    case RPM_STRING_TYPE:
        if (tagtype)
            val = tagtype(RPM_STRING_ARRAY_TYPE, data, buf, tag->pad,  0);

        if (!val) {
            strcat(buf, "s");

            len = strlen(data) + tag->pad + 20;
            val = xmalloc(len);
            sprintf(val, buf, data);
        }
        break;

    case RPM_CHAR_TYPE:
    case RPM_INT8_TYPE:
    case RPM_INT16_TYPE:
    case RPM_INT32_TYPE:
        switch (type) {
        case RPM_CHAR_TYPE:     
        case RPM_INT8_TYPE:     intVal = *(((int_8 *) data) + element); break;
        case RPM_INT16_TYPE:    intVal = *(((uint_16 *) data) + element); break;
        default:                /* keep -Wall quiet */
        case RPM_INT32_TYPE:    intVal = *(((int_32 *) data) + element); break;
        }

        if (tagtype)
            val = tagtype(RPM_INT32_TYPE, &intVal, buf, tag->pad,  element);

        if (!val) {
            strcat(buf, "d");
            len = 10 + tag->pad + 20;
            val = xmalloc(len);
            sprintf(val, buf, intVal);
        }
        break;

    default:
        val = xstrdup(_("(unknown type)"));
        break;
    }

    return val;
}

static const char * singleSprintf(Header h, struct sprintfToken * token,
                            const struct headerSprintfExtension * extensions,
                            struct extensionCache * extCache, int element)
                /*@modifies h, extCache->avail @*/
{
    char * val;
    const char * thisItem;
    int thisItemLen;
    int len, alloced;
    int i, j;
    int numElements;
    int type;
    struct sprintfToken * condFormat;
    int condNumFormats;

    /* we assume the token and header have been validated already! */

    switch (token->type) {
    case PTOK_NONE:
        break;

    case PTOK_STRING:
        val = xmalloc(token->u.string.len + 1);
        strcpy(val, token->u.string.string);
        break;

    case PTOK_TAG:
        val = formatValue(&token->u.tag, h, extensions, extCache,
                          token->u.tag.justOne ? 0 : element);
        break;

    case PTOK_COND:
        if (token->u.cond.tag.ext ||
            headerIsEntry(h, token->u.cond.tag.tag)) {
            condFormat = token->u.cond.ifFormat;
            condNumFormats = token->u.cond.numIfTokens;
        } else {
            condFormat = token->u.cond.elseFormat;
            condNumFormats = token->u.cond.numElseTokens;
        }

        alloced = condNumFormats * 20;
        val = xmalloc(alloced ? alloced : 1);
        *val = '\0';
        len = 0;

        for (i = 0; i < condNumFormats; i++) {
            thisItem = singleSprintf(h, condFormat + i, 
                                     extensions, extCache, element);
            thisItemLen = strlen(thisItem);
            if ((thisItemLen + len) >= alloced) {
                alloced = (thisItemLen + len) + 200;
                val = xrealloc(val, alloced);   
            }
            strcat(val, thisItem);
            len += thisItemLen;
            free((void *)thisItem);
        }

        break;

    case PTOK_ARRAY:
        numElements = -1;
        for (i = 0; i < token->u.array.numTokens; i++) {
            if (token->u.array.format[i].type != PTOK_TAG ||
                token->u.array.format[i].u.tag.arrayCount ||
                token->u.array.format[i].u.tag.justOne) continue;

            if (token->u.array.format[i].u.tag.ext) {
                const void * data;
                if (getExtension(h, token->u.array.format[i].u.tag.ext,
                                 &type, &data, &numElements, 
                                 extCache + 
                                   token->u.array.format[i].u.tag.extNum))
                     continue;
            } else {
                if (!headerGetEntry(h, token->u.array.format[i].u.tag.tag, 
                                    &type, (void **) &val, &numElements))
                    continue;
                val = headerFreeData(val, type);
            } 
            break;
        }

        if (numElements == -1) {
            val = xstrdup("(none)");    /* XXX i18n? NO!, sez; gafton */
        } else {
            alloced = numElements * token->u.array.numTokens * 20;
            val = xmalloc(alloced);
            *val = '\0';
            len = 0;

            for (j = 0; j < numElements; j++) {
                for (i = 0; i < token->u.array.numTokens; i++) {
                    thisItem = singleSprintf(h, token->u.array.format + i, 
                                             extensions, extCache, j);
                    thisItemLen = strlen(thisItem);
                    if ((thisItemLen + len) >= alloced) {
                        alloced = (thisItemLen + len) + 200;
                        val = xrealloc(val, alloced);   
                    }
                    strcat(val, thisItem);
                    len += thisItemLen;
                    free((void *)thisItem);
                }
            }
        }
           
        break;
    }

    return val;
}

static struct extensionCache * allocateExtensionCache(
                     const struct headerSprintfExtension * extensions)
                /*@*/
{
    const struct headerSprintfExtension * ext = extensions;
    int i = 0;

    while (ext->type != HEADER_EXT_LAST) {
        i++;
        if (ext->type == HEADER_EXT_MORE)
            ext = ext->u.more;
        else
            ext++;
    }

    return xcalloc(i, sizeof(struct extensionCache));
}

static void freeExtensionCache(const struct headerSprintfExtension * extensions,
                        /*@only@*/struct extensionCache * cache)
{
    const struct headerSprintfExtension * ext = extensions;
    int i = 0;

    while (ext->type != HEADER_EXT_LAST) {
        if (cache[i].freeit) free((void *)cache[i].data);

        i++;
        if (ext->type == HEADER_EXT_MORE)
            ext = ext->u.more;
        else
            ext++;
    }

    free(cache);
}

char * headerSprintf(Header h, const char * origFmt, 
                     const struct headerTagTableEntry * tags,
                     const struct headerSprintfExtension * extensions,
                     const char ** errmsg)
{
    char * fmtString;
    struct sprintfToken * format;
    int numTokens;
    char * answer;
    int answerLength;
    int answerAlloced;
    int i;
    struct extensionCache * extCache;
 
    /*fmtString = escapeString(origFmt);*/
    fmtString = xstrdup(origFmt);
   
    if (parseFormat(fmtString, tags, extensions, &format, &numTokens, 
                    NULL, PARSER_BEGIN, errmsg)) {
        free(fmtString);
        return NULL;
    }

    extCache = allocateExtensionCache(extensions);

    answerAlloced = 1024;
    answerLength = 0;
    answer = xmalloc(answerAlloced);
    *answer = '\0';

    for (i = 0; i < numTokens; i++) {
        const char * piece;
        int pieceLength;

        piece = singleSprintf(h, format + i, extensions, extCache, 0);
        if (piece) {
            pieceLength = strlen(piece);
            if ((answerLength + pieceLength) >= answerAlloced) {
                while ((answerLength + pieceLength) >= answerAlloced) 
                    answerAlloced += 1024;
                answer = xrealloc(answer, answerAlloced);
            }

            strcat(answer, piece);
            answerLength += pieceLength;
            free((void *)piece);
        }
    }

    free(fmtString);
    freeExtensionCache(extensions, extCache);
    free(format);

    return answer;
}

static char * octalFormat(int_32 type, const void * data, 
                char * formatPrefix, int padding, /*@unused@*/int element)
                /*@modifies formatPrefix @*/
{
    char * val;

    if (type != RPM_INT32_TYPE) {
        val = xstrdup(_("(not a number)"));
    } else {
        val = xmalloc(20 + padding);
        strcat(formatPrefix, "o");
        sprintf(val, formatPrefix, *((int_32 *) data));
    }

    return val;
}

static char * hexFormat(int_32 type, const void * data, 
                char * formatPrefix, int padding, /*@unused@*/int element)
                /*@modifies formatPrefix @*/
{
    char * val;

    if (type != RPM_INT32_TYPE) {
        val = xstrdup(_("(not a number)"));
    } else {
        val = xmalloc(20 + padding);
        strcat(formatPrefix, "x");
        sprintf(val, formatPrefix, *((int_32 *) data));
    }

    return val;
}

static char * realDateFormat(int_32 type, const void * data, 
                char * formatPrefix, int padding, /*@unused@*/int element,
                char * strftimeFormat)
                /*@modifies formatPrefix @*/
{
    char * val;
    struct tm * tstruct;
    char buf[50];

    if (type != RPM_INT32_TYPE) {
        val = xstrdup(_("(not a number)"));
    } else {
        val = xmalloc(50 + padding);
        strcat(formatPrefix, "s");

        /* this is important if sizeof(int_32) ! sizeof(time_t) */
        {   time_t dateint = *((int_32 *) data);
            tstruct = localtime(&dateint);
        }
        (void)strftime(buf, sizeof(buf) - 1, strftimeFormat, tstruct);
        sprintf(val, formatPrefix, buf);
    }

    return val;
}

static char * dateFormat(int_32 type, const void * data, 
                         char * formatPrefix, int padding, int element)
                /*@modifies formatPrefix @*/
{
    return realDateFormat(type, data, formatPrefix, padding, element, "%c");
}

static char * dayFormat(int_32 type, const void * data, 
                         char * formatPrefix, int padding, int element)
                /*@modifies formatPrefix @*/
{
    return realDateFormat(type, data, formatPrefix, padding, element, 
                          "%a %b %d %Y");
}

static char * shescapeFormat(int_32 type, const void * data, 
                char * formatPrefix, int padding, /*@unused@*/int element)
                /*@modifies formatPrefix @*/
{
    char * result, * dst, * src, * buf;

    if (type == RPM_INT32_TYPE) {
        result = xmalloc(padding + 20);
        strcat(formatPrefix, "d");
        sprintf(result, formatPrefix, *((int_32 *) data));
    } else {
        buf = alloca(strlen(data) + padding + 2);
        strcat(formatPrefix, "s");
        sprintf(buf, formatPrefix, data);

        result = dst = xmalloc(strlen(buf) * 4 + 3);
        *dst++ = '\'';
        for (src = buf; *src; src++) {
            if (*src == '\'') {
                *dst++ = '\'';
                *dst++ = '\\';
                *dst++ = '\'';
                *dst++ = '\'';
            } else {
                *dst++ = *src;
            }
        }
        *dst++ = '\'';
        *dst = '\0';

    }

    return result;
}

const struct headerSprintfExtension headerDefaultFormats[] = {
    { HEADER_EXT_FORMAT, "octal", { octalFormat } },
    { HEADER_EXT_FORMAT, "hex", { hexFormat } },
    { HEADER_EXT_FORMAT, "date", { dateFormat } },
    { HEADER_EXT_FORMAT, "day", { dayFormat } },
    { HEADER_EXT_FORMAT, "shescape", { shescapeFormat } },
    { HEADER_EXT_LAST, NULL, { NULL } }
};

void headerCopyTags(Header headerFrom, Header headerTo, int *tagstocopy)
{
    int *p;

    if (headerFrom == headerTo)
        return;

    for (p = tagstocopy; *p != 0; p++) {
        char *s;
        int type, count;
        if (headerIsEntry(headerTo, *p))
            continue;
        if (!headerGetEntryMinMemory(headerFrom, *p, &type,
                                (const void **) &s, &count))
            continue;
        headerAddEntry(headerTo, *p, type, s, count);
        s = headerFreeData(s, type);
    }
}

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