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Remove old zip base skew hack

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Since 8ff48201ca we no longer need the
hack where, when running .com.dbg files, we scanned for the embedded
.com file offset, and then computed zip offsets realtive to that. It
wasn't very reliable in the first place, and was causing issues with
running our new .com.dbg executables, which are true zip files.
This commit is contained in:
Justine Tunney 2023-06-17 04:20:16 -07:00
parent 207e18a060
commit 52d28966f7
No known key found for this signature in database
GPG key ID: BE714B4575D6E328
10 changed files with 134 additions and 238 deletions
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78
tool/build/zipbase.c
View file

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

5
tool/build/zipcopy.c
View file

@ -123,12 +123,15 @@ static void CopyZip(void) {
unsigned char *ineof, *stop, *eocd, *cdir, *lfile, *cfile;
// find zip eocd header
ineof = (unsigned char *)inmap + insize;
ineof = inmap + insize;
eocd = ineof - kZipCdirHdrMinSize;
stop = MAX(eocd - 65536, inmap);
for (;; --eocd) {
if (eocd < stop) return;
if (READ32LE(eocd) == kZipCdirHdrMagic) {
if (IsZipEocd32(inmap, insize, eocd - inmap) != kZipOk) {
Die(inpath, "found bad eocd record");
}
break;
}
}