mirror of
https://github.com/jart/cosmopolitan.git
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4a59210008
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.
78 lines
2.5 KiB
C
78 lines
2.5 KiB
C
#if 0
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/*─────────────────────────────────────────────────────────────────╗
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│ To the extent possible under law, Justine Tunney has waived │
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│ all copyright and related or neighboring rights to this file, │
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│ as it is written in the following disclaimers: │
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│ • http://unlicense.org/ │
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│ • http://creativecommons.org/publicdomain/zero/1.0/ │
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╚─────────────────────────────────────────────────────────────────*/
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#endif
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#include "libc/calls/calls.h"
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#include "libc/calls/struct/stat.h"
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#include "libc/log/check.h"
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#include "libc/macros.internal.h"
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#include "libc/runtime/runtime.h"
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#include "libc/stdio/stdio.h"
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#include "libc/sysv/consts/map.h"
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#include "libc/sysv/consts/o.h"
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#include "libc/sysv/consts/prot.h"
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#include "libc/zip.internal.h"
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int main(int argc, char *argv[]) {
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if (argc != 2) {
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fprintf(stderr, "usage: %s FOO.COM\n", argv[0]);
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fprintf(stderr,
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"prints lowest file offset (in decimal bytes) at which zip\n"
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"records exist within a .com, .com.dbg, or .zip file\n");
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exit(1);
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}
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int fd = open(argv[1], O_RDONLY);
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if (fd == -1) {
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perror(argv[1]);
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exit(1);
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}
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size_t n;
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struct stat st;
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CHECK_EQ(0, fstat(fd, &st));
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n = st.st_size;
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uint8_t *m;
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CHECK_NE(MAP_FAILED, (m = mmap(0, n, PROT_READ, MAP_PRIVATE, fd, 0)));
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int err;
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uint8_t *b, *d, *p;
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if ((p = FindEmbeddedApe(m, n))) {
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b = p;
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n -= p - m;
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} else {
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b = m;
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}
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if (!(d = GetZipEocd(b, n, &err))) {
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fprintf(stderr, "%s: couldn't locate central directory [zip error %d]\n",
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argv[1], err);
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exit(1);
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}
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size_t zsize = n;
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uint8_t *zmap = m;
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uint8_t *zbase = b;
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uint8_t *zcdir = d;
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DCHECK(IsZipEocd32(zbase, zsize, zcdir - zbase) == kZipOk ||
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IsZipEocd64(zbase, zsize, zcdir - zbase) == kZipOk);
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uint64_t cf;
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uint64_t lf;
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uint64_t minzipoffset;
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n = GetZipCdirRecords(zcdir);
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minzipoffset = cf = GetZipCdirOffset(zcdir);
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for (; n--; cf += ZIP_CFILE_HDRSIZE(zbase + cf)) {
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CHECK_EQ(kZipCfileHdrMagic, ZIP_CFILE_MAGIC(zbase + cf));
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lf = GetZipCfileOffset(zbase + cf);
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minzipoffset = MIN(minzipoffset, lf);
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}
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printf("%ld\n", (zbase + minzipoffset) - m);
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}
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