mpv/misc/path_utils.c

303 lines
8.2 KiB
C

/*
* Path utility functions
*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include "config.h"
#include "mpv_talloc.h"
#include "common/common.h"
#include "osdep/io.h"
#include "misc/ctype.h"
#include "misc/path_utils.h"
#if defined(HAVE_PATHCCH) && HAVE_PATHCCH
#include <windows.h>
#include <pathcch.h>
#endif
char *mp_basename(const char *path)
{
char *s;
#if HAVE_DOS_PATHS
if (!mp_is_url(bstr0(path))) {
s = strrchr(path, '\\');
if (s)
path = s + 1;
s = strrchr(path, ':');
if (s)
path = s + 1;
}
#endif
s = strrchr(path, '/');
return s ? s + 1 : (char *)path;
}
struct bstr mp_dirname(const char *path)
{
struct bstr ret = {
(uint8_t *)path, mp_basename(path) - path
};
if (ret.len == 0)
return bstr0(".");
return ret;
}
#if HAVE_DOS_PATHS
static const char mp_path_separators[] = "\\/";
#else
static const char mp_path_separators[] = "/";
#endif
// Mutates path and removes a trailing '/' (or '\' on Windows)
void mp_path_strip_trailing_separator(char *path)
{
size_t len = strlen(path);
if (len > 0 && strchr(mp_path_separators, path[len - 1]))
path[len - 1] = '\0';
}
char *mp_splitext(const char *path, bstr *root)
{
assert(path);
int skip = (*path == '.'); // skip leading dot for "hidden" unix files
const char *split = strrchr(path + skip, '.');
if (!split || !split[1] || strchr(split, '/'))
return NULL;
if (root)
*root = (bstr){(char *)path, split - path};
return (char *)split + 1;
}
bool mp_path_is_absolute(struct bstr path)
{
if (path.len && strchr(mp_path_separators, path.start[0]))
return true;
#if HAVE_DOS_PATHS
// Note: "X:filename" is a path relative to the current working directory
// of drive X, and thus is not an absolute path. It needs to be
// followed by \ or /.
if (path.len >= 3 && path.start[1] == ':' &&
strchr(mp_path_separators, path.start[2]))
return true;
#endif
return false;
}
char *mp_path_join_bstr(void *talloc_ctx, struct bstr p1, struct bstr p2)
{
if (p1.len == 0)
return bstrdup0(talloc_ctx, p2);
if (p2.len == 0)
return bstrdup0(talloc_ctx, p1);
if (mp_path_is_absolute(p2))
return bstrdup0(talloc_ctx, p2);
bool have_separator = strchr(mp_path_separators, p1.start[p1.len - 1]);
#if HAVE_DOS_PATHS
// "X:" only => path relative to "X:" current working directory.
if (p1.len == 2 && p1.start[1] == ':')
have_separator = true;
#endif
return talloc_asprintf(talloc_ctx, "%.*s%s%.*s", BSTR_P(p1),
have_separator ? "" : "/", BSTR_P(p2));
}
char *mp_path_join(void *talloc_ctx, const char *p1, const char *p2)
{
return mp_path_join_bstr(talloc_ctx, bstr0(p1), bstr0(p2));
}
char *mp_getcwd(void *talloc_ctx)
{
char *e_wd = getenv("PWD");
if (e_wd)
return talloc_strdup(talloc_ctx, e_wd);
char *wd = talloc_array(talloc_ctx, char, 20);
while (getcwd(wd, talloc_get_size(wd)) == NULL) {
if (errno != ERANGE) {
talloc_free(wd);
return NULL;
}
wd = talloc_realloc(talloc_ctx, wd, char, talloc_get_size(wd) * 2);
}
return wd;
}
char *mp_normalize_path(void *talloc_ctx, const char *path)
{
if (!path)
return NULL;
if (mp_is_url(bstr0(path)))
return talloc_strdup(talloc_ctx, path);
if (!mp_path_is_absolute(bstr0(path))) {
char *cwd = mp_getcwd(talloc_ctx);
if (!cwd)
return NULL;
path = mp_path_join(talloc_ctx, cwd, path);
}
#if defined(HAVE_PATHCCH) && HAVE_PATHCCH
wchar_t *pathw = mp_from_utf8(NULL, path);
wchar_t *read = pathw, *write = pathw;
wchar_t prev = '\0';
// preserve leading double backslashes
if (read[0] == '\\' && read[1] == '\\') {
prev = '\\';
write += 2;
read += 2;
}
wchar_t curr;
while ((curr = *read)) {
if (curr == '/')
curr = '\\';
if (curr != '\\' || prev != '\\')
*write++ = curr;
prev = curr;
read++;
}
*write = '\0';
size_t max_size = wcslen(pathw) + 1;
wchar_t *pathc = talloc_array(NULL, wchar_t, max_size);
HRESULT hr = PathCchCanonicalizeEx(pathc, max_size, pathw, PATHCCH_ALLOW_LONG_PATHS);
char *ret = SUCCEEDED(hr) ? mp_to_utf8(talloc_ctx, pathc) : talloc_strdup(talloc_ctx, path);
talloc_free(pathw);
talloc_free(pathc);
return ret;
#elif HAVE_DOS_PATHS
return talloc_strdup(talloc_ctx, path);
#else
char *result = talloc_strdup(talloc_ctx, "");
const char *next;
const char *end = path + strlen(path);
for (const char *ptr = path; ptr < end; ptr = next + 1) {
next = memchr(ptr, '/', end - ptr);
if (next == NULL)
next = end;
switch (next - ptr) {
case 0:
continue;
case 1:
if (ptr[0] == '.')
continue;
break;
case 2:
// Normalizing symlink/.. results in a wrong path: if the
// current working directory is /tmp/foo, and it is a symlink to
// /usr/bin, mpv ../file.mkv opens /usr/file.mkv, so we can't
// normalize the path to /tmp/file.mkv. Resolve symlinks to fix
// this. Otherwise we don't use realpath so users can use
// symlinks e.g. to hide how media files are distributed over
// real storage and move them while still resuming playback as
// long as the symlinked path doesn't change.
if (ptr[0] == '.' && ptr[1] == '.') {
char *tmp_result = realpath(path, NULL);
result = talloc_strdup(talloc_ctx, tmp_result);
free(tmp_result);
return result;
}
}
result = talloc_strdup_append_buffer(result, "/");
result = talloc_strndup_append_buffer(result, ptr, next - ptr);
}
return result;
#endif
}
bool mp_path_exists(const char *path)
{
struct stat st;
return path && stat(path, &st) == 0;
}
bool mp_path_isdir(const char *path)
{
struct stat st;
return stat(path, &st) == 0 && S_ISDIR(st.st_mode);
}
// Return false if it's considered a normal local filesystem path.
bool mp_is_url(bstr path)
{
int proto = bstr_find0(path, "://");
if (proto < 1)
return false;
// Per RFC3986, the first character of the protocol must be alphabetic.
// The rest must be alphanumeric plus -, + and .
for (int i = 0; i < proto; i++) {
unsigned char c = path.start[i];
if ((i == 0 && !mp_isalpha(c)) ||
(!mp_isalnum(c) && c != '.' && c != '-' && c != '+'))
{
return false;
}
}
return true;
}
// Return the protocol part of path, e.g. "http" if path is "http://...".
// On success, out_url (if not NULL) is set to the part after the "://".
bstr mp_split_proto(bstr path, bstr *out_url)
{
if (!mp_is_url(path))
return (bstr){0};
bstr r;
bstr_split_tok(path, "://", &r, out_url ? out_url : &(bstr){0});
return r;
}
void mp_mkdirp(const char *dir)
{
char *path = talloc_strdup(NULL, dir);
char *cdir = path + 1;
while (cdir) {
cdir = strchr(cdir, '/');
if (cdir)
*cdir = 0;
mkdir(path, 0700);
if (cdir)
*cdir++ = '/';
}
talloc_free(path);
}