git/builtin-cat-file.c
Rene Scharfe 7230e6d042 Add write_or_die(), a helper function
The little helper write_or_die() won't come back with bad news about
full disks or broken pipes.  It either succeeds or terminates the
program, making additional error handling unnecessary.

This patch adds the new function and uses it to replace two similar
ones (the one in tar-tree originally has been copied from cat-file
btw.).  I chose to add the fd parameter which both lacked to make
write_or_die() just as flexible as write() and thus suitable for
lib-ification.

There is a regression: error messages emitted by this function don't
show the program name, while the replaced two functions did.  That's
acceptable, I think; a lot of other functions do the same.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-08-21 20:22:23 -07:00

150 lines
3.2 KiB
C

/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.h"
#include "exec_cmd.h"
#include "tag.h"
#include "tree.h"
#include "builtin.h"
static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
{
/* the parser in tag.c is useless here. */
const char *endp = buf + size;
const char *cp = buf;
while (cp < endp) {
char c = *cp++;
if (c != '\n')
continue;
if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
const char *tagger = cp;
/* Found the tagger line. Copy out the contents
* of the buffer so far.
*/
write_or_die(1, buf, cp - buf);
/*
* Do something intelligent, like pretty-printing
* the date.
*/
while (cp < endp) {
if (*cp++ == '\n') {
/* tagger to cp is a line
* that has ident and time.
*/
const char *sp = tagger;
char *ep;
unsigned long date;
long tz;
while (sp < cp && *sp != '>')
sp++;
if (sp == cp) {
/* give up */
write_or_die(1, tagger,
cp - tagger);
break;
}
while (sp < cp &&
!('0' <= *sp && *sp <= '9'))
sp++;
write_or_die(1, tagger, sp - tagger);
date = strtoul(sp, &ep, 10);
tz = strtol(ep, NULL, 10);
sp = show_date(date, tz);
write_or_die(1, sp, strlen(sp));
xwrite(1, "\n", 1);
break;
}
}
break;
}
if (cp < endp && *cp == '\n')
/* end of header */
break;
}
/* At this point, we have copied out the header up to the end of
* the tagger line and cp points at one past \n. It could be the
* next header line after the tagger line, or it could be another
* \n that marks the end of the headers. We need to copy out the
* remainder as is.
*/
if (cp < endp)
write_or_die(1, cp, endp - cp);
}
int cmd_cat_file(int argc, const char **argv, const char *prefix)
{
unsigned char sha1[20];
char type[20];
void *buf;
unsigned long size;
int opt;
git_config(git_default_config);
if (argc != 3)
usage("git-cat-file [-t|-s|-e|-p|<type>] <sha1>");
if (get_sha1(argv[2], sha1))
die("Not a valid object name %s", argv[2]);
opt = 0;
if ( argv[1][0] == '-' ) {
opt = argv[1][1];
if ( !opt || argv[1][2] )
opt = -1; /* Not a single character option */
}
buf = NULL;
switch (opt) {
case 't':
if (!sha1_object_info(sha1, type, NULL)) {
printf("%s\n", type);
return 0;
}
break;
case 's':
if (!sha1_object_info(sha1, type, &size)) {
printf("%lu\n", size);
return 0;
}
break;
case 'e':
return !has_sha1_file(sha1);
case 'p':
if (sha1_object_info(sha1, type, NULL))
die("Not a valid object name %s", argv[2]);
/* custom pretty-print here */
if (!strcmp(type, tree_type))
return cmd_ls_tree(2, argv + 1, NULL);
buf = read_sha1_file(sha1, type, &size);
if (!buf)
die("Cannot read object %s", argv[2]);
if (!strcmp(type, tag_type)) {
pprint_tag(sha1, buf, size);
return 0;
}
/* otherwise just spit out the data */
break;
case 0:
buf = read_object_with_reference(sha1, argv[1], &size, NULL);
break;
default:
die("git-cat-file: unknown option: %s\n", argv[1]);
}
if (!buf)
die("git-cat-file %s: bad file", argv[2]);
write_or_die(1, buf, size);
return 0;
}