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#include "cache.h"
/*
* Do not use this for inspecting *tracked* content. When path is a
* symlink to a directory, we do not want to say it is a directory when
* dealing with tracked content in the working tree.
*/
int is_directory(const char *path)
{
struct stat st;
return (!stat(path, &st) && S_ISDIR(st.st_mode));
}
/* We allow "recursive" symbolic links. Only within reason, though. */
#define MAXDEPTH 5
/*
* Return the real path (i.e., absolute path, with symlinks resolved
* and extra slashes removed) equivalent to the specified path. (If
* you want an absolute path but don't mind links, use
* absolute_path().) The return value is a pointer to a static
* buffer.
*
* The input and all intermediate paths must be shorter than MAX_PATH.
* The directory part of path (i.e., everything up to the last
* dir_sep) must denote a valid, existing directory, but the last
* component need not exist. If die_on_error is set, then die with an
* informative error message if there is a problem. Otherwise, return
* NULL on errors (without generating any output).
*
* If path is our buffer, then return path, as it's already what the
* user wants.
*/
static const char *real_path_internal(const char *path, int die_on_error)
{
static char bufs[2][PATH_MAX + 1], *buf = bufs[0], *next_buf = bufs[1];
char *retval = NULL;
/*
* If we have to temporarily chdir(), store the original CWD
* here so that we can chdir() back to it at the end of the
* function:
*/
char cwd[1024] = "";
int buf_index = 1;
int depth = MAXDEPTH;
char *last_elem = NULL;
struct stat st;
/* We've already done it */
if (path == buf || path == next_buf)
return path;
if (!*path) {
if (die_on_error)
die("The empty string is not a valid path");
else
goto error_out;
}
if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) {
if (die_on_error)
die("Too long path: %.*s", 60, path);
else
goto error_out;
}
while (depth--) {
if (!is_directory(buf)) {
char *last_slash = find_last_dir_sep(buf);
if (last_slash) {
last_elem = xstrdup(last_slash + 1);
last_slash[1] = '\0';
} else {
last_elem = xstrdup(buf);
*buf = '\0';
}
}
if (*buf) {
if (!*cwd && !getcwd(cwd, sizeof(cwd))) {
if (die_on_error)
die_errno("Could not get current working directory");
else
goto error_out;
}
if (chdir(buf)) {
if (die_on_error)
die_errno("Could not switch to '%s'", buf);
else
goto error_out;
}
}
if (!getcwd(buf, PATH_MAX)) {
if (die_on_error)
die_errno("Could not get current working directory");
else
goto error_out;
}
if (last_elem) {
size_t len = strlen(buf);
if (len + strlen(last_elem) + 2 > PATH_MAX) {
if (die_on_error)
die("Too long path name: '%s/%s'",
buf, last_elem);
else
goto error_out;
}
if (len && !is_dir_sep(buf[len - 1]))
buf[len++] = '/';
strcpy(buf + len, last_elem);
free(last_elem);
last_elem = NULL;
}
if (!lstat(buf, &st) && S_ISLNK(st.st_mode)) {
ssize_t len = readlink(buf, next_buf, PATH_MAX);
if (len < 0) {
if (die_on_error)
die_errno("Invalid symlink '%s'", buf);
else
goto error_out;
}
if (PATH_MAX <= len) {
if (die_on_error)
die("symbolic link too long: %s", buf);
else
goto error_out;
}
next_buf[len] = '\0';
buf = next_buf;
buf_index = 1 - buf_index;
next_buf = bufs[buf_index];
} else
break;
}
retval = buf;
error_out:
free(last_elem);
if (*cwd && chdir(cwd))
die_errno("Could not change back to '%s'", cwd);
return retval;
}
const char *real_path(const char *path)
{
return real_path_internal(path, 1);
}
const char *real_path_if_valid(const char *path)
{
return real_path_internal(path, 0);
}
static const char *get_pwd_cwd(void)
{
static char cwd[PATH_MAX + 1];
char *pwd;
struct stat cwd_stat, pwd_stat;
if (getcwd(cwd, PATH_MAX) == NULL)
return NULL;
pwd = getenv("PWD");
if (pwd && strcmp(pwd, cwd)) {
stat(cwd, &cwd_stat);
if ((cwd_stat.st_dev || cwd_stat.st_ino) &&
!stat(pwd, &pwd_stat) &&
pwd_stat.st_dev == cwd_stat.st_dev &&
pwd_stat.st_ino == cwd_stat.st_ino) {
strlcpy(cwd, pwd, PATH_MAX);
}
}
return cwd;
}
/*
* Use this to get an absolute path from a relative one. If you want
* to resolve links, you should use real_path.
*
* If the path is already absolute, then return path. As the user is
* never meant to free the return value, we're safe.
*/
const char *absolute_path(const char *path)
{
static char buf[PATH_MAX + 1];
if (!*path) {
die("The empty string is not a valid path");
} else if (is_absolute_path(path)) {
if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
die("Too long path: %.*s", 60, path);
} else {
size_t len;
const char *fmt;
const char *cwd = get_pwd_cwd();
if (!cwd)
die_errno("Cannot determine the current working directory");
len = strlen(cwd);
fmt = (len > 0 && is_dir_sep(cwd[len - 1])) ? "%s%s" : "%s/%s";
if (snprintf(buf, PATH_MAX, fmt, cwd, path) >= PATH_MAX)
die("Too long path: %.*s", 60, path);
}
return buf;
}
/*
* Unlike prefix_path, this should be used if the named file does
* not have to interact with index entry; i.e. name of a random file
* on the filesystem.
*/
const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
{
static char path[PATH_MAX];
#ifndef GIT_WINDOWS_NATIVE
if (!pfx_len || is_absolute_path(arg))
return arg;
memcpy(path, pfx, pfx_len);
strcpy(path + pfx_len, arg);
#else
char *p;
/* don't add prefix to absolute paths, but still replace '\' by '/' */
if (is_absolute_path(arg))
pfx_len = 0;
else if (pfx_len)
memcpy(path, pfx, pfx_len);
strcpy(path + pfx_len, arg);
for (p = path + pfx_len; *p; p++)
if (*p == '\\')
*p = '/';
#endif
return path;
}
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