git/builtin/check-ref-format.c
Jeff King 3733e69464 use xmallocz to avoid size arithmetic
We frequently allocate strings as xmalloc(len + 1), where
the extra 1 is for the NUL terminator. This can be done more
simply with xmallocz, which also checks for integer
overflow.

There's no case where switching xmalloc(n+1) to xmallocz(n)
is wrong; the result is the same length, and malloc made no
guarantees about what was in the buffer anyway. But in some
cases, we can stop manually placing NUL at the end of the
allocated buffer. But that's only safe if it's clear that
the contents will always fill the buffer.

In each case where this patch does so, I manually examined
the control flow, and I tried to err on the side of caution.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00

89 lines
2.1 KiB
C

/*
* GIT - The information manager from hell
*/
#include "cache.h"
#include "refs.h"
#include "builtin.h"
#include "strbuf.h"
static const char builtin_check_ref_format_usage[] =
"git check-ref-format [--normalize] [<options>] <refname>\n"
" or: git check-ref-format --branch <branchname-shorthand>";
/*
* Return a copy of refname but with leading slashes removed and runs
* of adjacent slashes replaced with single slashes.
*
* This function is similar to normalize_path_copy(), but stripped down
* to meet check_ref_format's simpler needs.
*/
static char *collapse_slashes(const char *refname)
{
char *ret = xmallocz(strlen(refname));
char ch;
char prev = '/';
char *cp = ret;
while ((ch = *refname++) != '\0') {
if (prev == '/' && ch == prev)
continue;
*cp++ = ch;
prev = ch;
}
*cp = '\0';
return ret;
}
static int check_ref_format_branch(const char *arg)
{
struct strbuf sb = STRBUF_INIT;
int nongit;
setup_git_directory_gently(&nongit);
if (strbuf_check_branch_ref(&sb, arg))
die("'%s' is not a valid branch name", arg);
printf("%s\n", sb.buf + 11);
return 0;
}
int cmd_check_ref_format(int argc, const char **argv, const char *prefix)
{
int i;
int normalize = 0;
int flags = 0;
const char *refname;
if (argc == 2 && !strcmp(argv[1], "-h"))
usage(builtin_check_ref_format_usage);
if (argc == 3 && !strcmp(argv[1], "--branch"))
return check_ref_format_branch(argv[2]);
for (i = 1; i < argc && argv[i][0] == '-'; i++) {
if (!strcmp(argv[i], "--normalize") || !strcmp(argv[i], "--print"))
normalize = 1;
else if (!strcmp(argv[i], "--allow-onelevel"))
flags |= REFNAME_ALLOW_ONELEVEL;
else if (!strcmp(argv[i], "--no-allow-onelevel"))
flags &= ~REFNAME_ALLOW_ONELEVEL;
else if (!strcmp(argv[i], "--refspec-pattern"))
flags |= REFNAME_REFSPEC_PATTERN;
else
usage(builtin_check_ref_format_usage);
}
if (! (i == argc - 1))
usage(builtin_check_ref_format_usage);
refname = argv[i];
if (normalize)
refname = collapse_slashes(refname);
if (check_refname_format(refname, flags))
return 1;
if (normalize)
printf("%s\n", refname);
return 0;
}