diff options
Diffstat (limited to 'libzipfile/centraldir.c')
| -rw-r--r-- | libzipfile/centraldir.c | 222 |
1 files changed, 0 insertions, 222 deletions
diff --git a/libzipfile/centraldir.c b/libzipfile/centraldir.c deleted file mode 100644 index 69cf47a..0000000 --- a/libzipfile/centraldir.c +++ /dev/null @@ -1,222 +0,0 @@ -#include "private.h"
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-
-#include <utils/Compat.h>
-
-enum {
- // finding the directory
- CD_SIGNATURE = 0x06054b50,
- EOCD_LEN = 22, // EndOfCentralDir len, excl. comment
- MAX_COMMENT_LEN = 65535,
- MAX_EOCD_SEARCH = MAX_COMMENT_LEN + EOCD_LEN,
-
- // central directory entries
- ENTRY_SIGNATURE = 0x02014b50,
- ENTRY_LEN = 46, // CentralDirEnt len, excl. var fields
-
- // local file header
- LFH_SIZE = 30,
-};
-
-unsigned int
-read_le_int(const unsigned char* buf)
-{
- return buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
-}
-
-unsigned int
-read_le_short(const unsigned char* buf)
-{
- return buf[0] | (buf[1] << 8);
-}
-
-static int
-read_central_dir_values(Zipfile* file, const unsigned char* buf, int len)
-{
- if (len < EOCD_LEN) {
- // looks like ZIP file got truncated
- fprintf(stderr, " Zip EOCD: expected >= %d bytes, found %d\n",
- EOCD_LEN, len);
- return -1;
- }
-
- file->disknum = read_le_short(&buf[0x04]);
- file->diskWithCentralDir = read_le_short(&buf[0x06]);
- file->entryCount = read_le_short(&buf[0x08]);
- file->totalEntryCount = read_le_short(&buf[0x0a]);
- file->centralDirSize = read_le_int(&buf[0x0c]);
- file->centralDirOffest = read_le_int(&buf[0x10]);
- file->commentLen = read_le_short(&buf[0x14]);
-
- if (file->commentLen > 0) {
- if (EOCD_LEN + file->commentLen > len) {
- fprintf(stderr, "EOCD(%d) + comment(%d) exceeds len (%d)\n",
- EOCD_LEN, file->commentLen, len);
- return -1;
- }
- file->comment = buf + EOCD_LEN;
- }
-
- return 0;
-}
-
-static int
-read_central_directory_entry(Zipfile* file, Zipentry* entry,
- const unsigned char** buf, ssize_t* len)
-{
- const unsigned char* p;
-
- unsigned short extraFieldLength;
- unsigned short fileCommentLength;
- unsigned long localHeaderRelOffset;
- unsigned int dataOffset;
-
- p = *buf;
-
- if (*len < ENTRY_LEN) {
- fprintf(stderr, "cde entry not large enough\n");
- return -1;
- }
-
- if (read_le_int(&p[0x00]) != ENTRY_SIGNATURE) {
- fprintf(stderr, "Whoops: didn't find expected signature\n");
- return -1;
- }
-
- entry->compressionMethod = read_le_short(&p[0x0a]);
- entry->compressedSize = read_le_int(&p[0x14]);
- entry->uncompressedSize = read_le_int(&p[0x18]);
- entry->fileNameLength = read_le_short(&p[0x1c]);
- extraFieldLength = read_le_short(&p[0x1e]);
- fileCommentLength = read_le_short(&p[0x20]);
- localHeaderRelOffset = read_le_int(&p[0x2a]);
-
- p += ENTRY_LEN;
-
- // filename
- if (entry->fileNameLength != 0) {
- entry->fileName = p;
- } else {
- entry->fileName = NULL;
- }
- p += entry->fileNameLength;
-
- // extra field
- p += extraFieldLength;
-
- // comment, if any
- p += fileCommentLength;
-
- *buf = p;
-
- // the size of the extraField in the central dir is how much data there is,
- // but the one in the local file header also contains some padding.
- p = file->buf + localHeaderRelOffset;
- extraFieldLength = read_le_short(&p[0x1c]);
-
- dataOffset = localHeaderRelOffset + LFH_SIZE
- + entry->fileNameLength + extraFieldLength;
- entry->data = file->buf + dataOffset;
-#if 0
- printf("file->buf=%p entry->data=%p dataOffset=%x localHeaderRelOffset=%d "
- "entry->fileNameLength=%d extraFieldLength=%d\n",
- file->buf, entry->data, dataOffset, localHeaderRelOffset,
- entry->fileNameLength, extraFieldLength);
-#endif
- return 0;
-}
-
-/*
- * Find the central directory and read the contents.
- *
- * The fun thing about ZIP archives is that they may or may not be
- * readable from start to end. In some cases, notably for archives
- * that were written to stdout, the only length information is in the
- * central directory at the end of the file.
- *
- * Of course, the central directory can be followed by a variable-length
- * comment field, so we have to scan through it backwards. The comment
- * is at most 64K, plus we have 18 bytes for the end-of-central-dir stuff
- * itself, plus apparently sometimes people throw random junk on the end
- * just for the fun of it.
- *
- * This is all a little wobbly. If the wrong value ends up in the EOCD
- * area, we're hosed. This appears to be the way that everbody handles
- * it though, so we're in pretty good company if this fails.
- */
-int
-read_central_dir(Zipfile *file)
-{
- int err;
-
- const unsigned char* buf = file->buf;
- ZD_TYPE bufsize = file->bufsize;
- const unsigned char* eocd;
- const unsigned char* p;
- const unsigned char* start;
- ssize_t len;
- int i;
-
- // too small to be a ZIP archive?
- if (bufsize < EOCD_LEN) {
- fprintf(stderr, "Length is " ZD " -- too small\n", bufsize);
- goto bail;
- }
-
- // find the end-of-central-dir magic
- if (bufsize > MAX_EOCD_SEARCH) {
- start = buf + bufsize - MAX_EOCD_SEARCH;
- } else {
- start = buf;
- }
- p = buf + bufsize - 4;
- while (p >= start) {
- if (*p == 0x50 && read_le_int(p) == CD_SIGNATURE) {
- eocd = p;
- break;
- }
- p--;
- }
- if (p < start) {
- fprintf(stderr, "EOCD not found, not Zip\n");
- goto bail;
- }
-
- // extract eocd values
- err = read_central_dir_values(file, eocd, (buf+bufsize)-eocd);
- if (err != 0) {
- goto bail;
- }
-
- if (file->disknum != 0
- || file->diskWithCentralDir != 0
- || file->entryCount != file->totalEntryCount) {
- fprintf(stderr, "Archive spanning not supported\n");
- goto bail;
- }
-
- // Loop through and read the central dir entries.
- p = buf + file->centralDirOffest;
- len = (buf+bufsize)-p;
- for (i=0; i < file->totalEntryCount; i++) {
- Zipentry* entry = malloc(sizeof(Zipentry));
- memset(entry, 0, sizeof(Zipentry));
-
- err = read_central_directory_entry(file, entry, &p, &len);
- if (err != 0) {
- fprintf(stderr, "read_central_directory_entry failed\n");
- free(entry);
- goto bail;
- }
-
- // add it to our list
- entry->next = file->entries;
- file->entries = entry;
- }
-
- return 0;
-bail:
- return -1;
-}
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