cosmopolitan/libc/str/iszipeocd32.c
Justine Tunney 4a59210008
Introduce #include <cosmo.h> to toolchain users
This change improves the way internal APIs are being hidden behind the
`COSMO` define. The cosmo.h header will take care of defining that, so
that a separate define statement isn't needed. This change also does a
lot more to define which APIs are standard, and which belong to Cosmo.
2023-06-09 18:03:05 -07:00

48 lines
2.6 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2021 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/zip.internal.h"
/**
* Determines if ZIP EOCD record seems legit.
*/
int IsZipEocd32(const uint8_t *p, size_t n, size_t i) {
if (i > n || n - i < kZipCdirHdrMinSize) {
return kZipErrorEocdOffsetOverflow;
}
if (READ32LE(p + i) != kZipCdirHdrMagic) {
return kZipErrorEocdMagicNotFound;
}
if (i + ZIP_CDIR_HDRSIZE(p + i) > n) {
return kZipErrorEocdSizeOverflow;
}
if (ZIP_CDIR_DISK(p + i) != ZIP_CDIR_STARTINGDISK(p + i)) {
return kZipErrorEocdDiskMismatch;
}
if (ZIP_CDIR_RECORDSONDISK(p + i) != ZIP_CDIR_RECORDS(p + i)) {
return kZipErrorCdirRecordsMismatch;
}
if (ZIP_CDIR_RECORDS(p + i) * kZipCfileHdrMinSize > ZIP_CDIR_SIZE(p + i)) {
return kZipErrorCdirRecordsOverflow;
}
if (ZIP_CDIR_OFFSET(p + i) + ZIP_CDIR_SIZE(p + i) > i) {
return kZipErrorCdirOffsetPastEocd;
}
return kZipOk;
}