git/compat/precompose_utf8.c
Jeff King fdf729661a probe_utf8_pathname_composition: use internal strbuf
When we are initializing a .git directory, we may call
probe_utf8_pathname_composition to detect utf8 mangling. We
pass in a path buffer for it to use, and it blindly
strcpy()s into it, not knowing whether the buffer is large
enough to hold the result or not.

In practice this isn't a big deal, because the buffer we
pass in already contains "$GIT_DIR/config", and we append
only a few extra bytes to it. But we can easily do the right
thing just by calling git_path_buf ourselves. Technically
this results in a different pathname (before we appended our
utf8 characters to the "config" path, and now they get their
own files in $GIT_DIR), but that should not matter for our
purposes.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05 11:06:49 -07:00

183 lines
4.6 KiB
C

/*
* Converts filenames from decomposed unicode into precomposed unicode.
* Used on MacOS X.
*/
#define PRECOMPOSE_UNICODE_C
#include "cache.h"
#include "utf8.h"
#include "precompose_utf8.h"
typedef char *iconv_ibp;
static const char *repo_encoding = "UTF-8";
static const char *path_encoding = "UTF-8-MAC";
static size_t has_non_ascii(const char *s, size_t maxlen, size_t *strlen_c)
{
const uint8_t *ptr = (const uint8_t *)s;
size_t strlen_chars = 0;
size_t ret = 0;
if (!ptr || !*ptr)
return 0;
while (*ptr && maxlen) {
if (*ptr & 0x80)
ret++;
strlen_chars++;
ptr++;
maxlen--;
}
if (strlen_c)
*strlen_c = strlen_chars;
return ret;
}
void probe_utf8_pathname_composition(void)
{
struct strbuf path = STRBUF_INIT;
static const char *auml_nfc = "\xc3\xa4";
static const char *auml_nfd = "\x61\xcc\x88";
int output_fd;
if (precomposed_unicode != -1)
return; /* We found it defined in the global config, respect it */
git_path_buf(&path, "%s", auml_nfc);
output_fd = open(path.buf, O_CREAT|O_EXCL|O_RDWR, 0600);
if (output_fd >= 0) {
close(output_fd);
git_path_buf(&path, "%s", auml_nfd);
precomposed_unicode = access(path.buf, R_OK) ? 0 : 1;
git_config_set("core.precomposeunicode", precomposed_unicode ? "true" : "false");
git_path_buf(&path, "%s", auml_nfc);
if (unlink(path.buf))
die_errno(_("failed to unlink '%s'"), path.buf);
}
strbuf_release(&path);
}
void precompose_argv(int argc, const char **argv)
{
int i = 0;
const char *oldarg;
char *newarg;
iconv_t ic_precompose;
if (precomposed_unicode != 1)
return;
ic_precompose = iconv_open(repo_encoding, path_encoding);
if (ic_precompose == (iconv_t) -1)
return;
while (i < argc) {
size_t namelen;
oldarg = argv[i];
if (has_non_ascii(oldarg, (size_t)-1, &namelen)) {
newarg = reencode_string_iconv(oldarg, namelen, ic_precompose, NULL);
if (newarg)
argv[i] = newarg;
}
i++;
}
iconv_close(ic_precompose);
}
PREC_DIR *precompose_utf8_opendir(const char *dirname)
{
PREC_DIR *prec_dir = xmalloc(sizeof(PREC_DIR));
prec_dir->dirent_nfc = xmalloc(sizeof(dirent_prec_psx));
prec_dir->dirent_nfc->max_name_len = sizeof(prec_dir->dirent_nfc->d_name);
prec_dir->dirp = opendir(dirname);
if (!prec_dir->dirp) {
free(prec_dir->dirent_nfc);
free(prec_dir);
return NULL;
} else {
int ret_errno = errno;
prec_dir->ic_precompose = iconv_open(repo_encoding, path_encoding);
/* if iconv_open() fails, die() in readdir() if needed */
errno = ret_errno;
}
return prec_dir;
}
struct dirent_prec_psx *precompose_utf8_readdir(PREC_DIR *prec_dir)
{
struct dirent *res;
res = readdir(prec_dir->dirp);
if (res) {
size_t namelenz = strlen(res->d_name) + 1; /* \0 */
size_t new_maxlen = namelenz;
int ret_errno = errno;
if (new_maxlen > prec_dir->dirent_nfc->max_name_len) {
size_t new_len = sizeof(dirent_prec_psx) + new_maxlen -
sizeof(prec_dir->dirent_nfc->d_name);
prec_dir->dirent_nfc = xrealloc(prec_dir->dirent_nfc, new_len);
prec_dir->dirent_nfc->max_name_len = new_maxlen;
}
prec_dir->dirent_nfc->d_ino = res->d_ino;
prec_dir->dirent_nfc->d_type = res->d_type;
if ((precomposed_unicode == 1) && has_non_ascii(res->d_name, (size_t)-1, NULL)) {
if (prec_dir->ic_precompose == (iconv_t)-1) {
die("iconv_open(%s,%s) failed, but needed:\n"
" precomposed unicode is not supported.\n"
" If you want to use decomposed unicode, run\n"
" \"git config core.precomposeunicode false\"\n",
repo_encoding, path_encoding);
} else {
iconv_ibp cp = (iconv_ibp)res->d_name;
size_t inleft = namelenz;
char *outpos = &prec_dir->dirent_nfc->d_name[0];
size_t outsz = prec_dir->dirent_nfc->max_name_len;
errno = 0;
iconv(prec_dir->ic_precompose, &cp, &inleft, &outpos, &outsz);
if (errno || inleft) {
/*
* iconv() failed and errno could be E2BIG, EILSEQ, EINVAL, EBADF
* MacOS X avoids illegal byte sequemces.
* If they occur on a mounted drive (e.g. NFS) it is not worth to
* die() for that, but rather let the user see the original name
*/
namelenz = 0; /* trigger strlcpy */
}
}
} else
namelenz = 0;
if (!namelenz)
strlcpy(prec_dir->dirent_nfc->d_name, res->d_name,
prec_dir->dirent_nfc->max_name_len);
errno = ret_errno;
return prec_dir->dirent_nfc;
}
return NULL;
}
int precompose_utf8_closedir(PREC_DIR *prec_dir)
{
int ret_value;
int ret_errno;
ret_value = closedir(prec_dir->dirp);
ret_errno = errno;
if (prec_dir->ic_precompose != (iconv_t)-1)
iconv_close(prec_dir->ic_precompose);
free(prec_dir->dirent_nfc);
free(prec_dir);
errno = ret_errno;
return ret_value;
}