Revert "compat: add strtok_r()"
[git/mingw.git] / abspath.c
blob40cdc46219d4eba87ba947d9f5556eb80dfdfa9b
1 #include "cache.h"
3 /*
4 * Do not use this for inspecting *tracked* content. When path is a
5 * symlink to a directory, we do not want to say it is a directory when
6 * dealing with tracked content in the working tree.
7 */
8 int is_directory(const char *path)
10 struct stat st;
11 return (!stat(path, &st) && S_ISDIR(st.st_mode));
14 /* We allow "recursive" symbolic links. Only within reason, though. */
15 #define MAXDEPTH 5
18 * Return the real path (i.e., absolute path, with symlinks resolved
19 * and extra slashes removed) equivalent to the specified path. (If
20 * you want an absolute path but don't mind links, use
21 * absolute_path().) The return value is a pointer to a static
22 * buffer.
24 * The input and all intermediate paths must be shorter than MAX_PATH.
25 * The directory part of path (i.e., everything up to the last
26 * dir_sep) must denote a valid, existing directory, but the last
27 * component need not exist. If die_on_error is set, then die with an
28 * informative error message if there is a problem. Otherwise, return
29 * NULL on errors (without generating any output).
31 * If path is our buffer, then return path, as it's already what the
32 * user wants.
34 static const char *real_path_internal(const char *path, int die_on_error)
36 static char bufs[2][PATH_MAX + 1], *buf = bufs[0], *next_buf = bufs[1];
37 char *retval = NULL;
40 * If we have to temporarily chdir(), store the original CWD
41 * here so that we can chdir() back to it at the end of the
42 * function:
44 char cwd[1024] = "";
46 int buf_index = 1;
48 int depth = MAXDEPTH;
49 char *last_elem = NULL;
50 struct stat st;
52 /* We've already done it */
53 if (path == buf || path == next_buf)
54 return path;
56 if (!*path) {
57 if (die_on_error)
58 die("The empty string is not a valid path");
59 else
60 goto error_out;
63 if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) {
64 if (die_on_error)
65 die("Too long path: %.*s", 60, path);
66 else
67 goto error_out;
70 while (depth--) {
71 if (!is_directory(buf)) {
72 char *last_slash = find_last_dir_sep(buf);
73 if (last_slash) {
74 last_elem = xstrdup(last_slash + 1);
75 last_slash[1] = '\0';
76 } else {
77 last_elem = xstrdup(buf);
78 *buf = '\0';
82 if (*buf) {
83 if (!*cwd && !getcwd(cwd, sizeof(cwd))) {
84 if (die_on_error)
85 die_errno("Could not get current working directory");
86 else
87 goto error_out;
90 if (chdir(buf)) {
91 if (die_on_error)
92 die_errno("Could not switch to '%s'", buf);
93 else
94 goto error_out;
97 if (!getcwd(buf, PATH_MAX)) {
98 if (die_on_error)
99 die_errno("Could not get current working directory");
100 else
101 goto error_out;
104 if (last_elem) {
105 size_t len = strlen(buf);
106 if (len + strlen(last_elem) + 2 > PATH_MAX) {
107 if (die_on_error)
108 die("Too long path name: '%s/%s'",
109 buf, last_elem);
110 else
111 goto error_out;
113 if (len && !is_dir_sep(buf[len-1]))
114 buf[len++] = '/';
115 strcpy(buf + len, last_elem);
116 free(last_elem);
117 last_elem = NULL;
120 if (!lstat(buf, &st) && S_ISLNK(st.st_mode)) {
121 ssize_t len = readlink(buf, next_buf, PATH_MAX);
122 if (len < 0) {
123 if (die_on_error)
124 die_errno("Invalid symlink '%s'", buf);
125 else
126 goto error_out;
128 if (PATH_MAX <= len) {
129 if (die_on_error)
130 die("symbolic link too long: %s", buf);
131 else
132 goto error_out;
134 next_buf[len] = '\0';
135 buf = next_buf;
136 buf_index = 1 - buf_index;
137 next_buf = bufs[buf_index];
138 } else
139 break;
142 retval = buf;
143 error_out:
144 free(last_elem);
145 if (*cwd && chdir(cwd))
146 die_errno ("Could not change back to '%s'", cwd);
148 return retval;
151 const char *real_path(const char *path)
153 return real_path_internal(path, 1);
156 const char *real_path_if_valid(const char *path)
158 return real_path_internal(path, 0);
161 static const char *get_pwd_cwd(void)
163 static char cwd[PATH_MAX + 1];
164 char *pwd;
165 struct stat cwd_stat, pwd_stat;
166 if (getcwd(cwd, PATH_MAX) == NULL)
167 return NULL;
168 pwd = getenv("PWD");
169 if (pwd && strcmp(pwd, cwd)) {
170 stat(cwd, &cwd_stat);
171 if ((cwd_stat.st_dev || cwd_stat.st_ino) &&
172 !stat(pwd, &pwd_stat) &&
173 pwd_stat.st_dev == cwd_stat.st_dev &&
174 pwd_stat.st_ino == cwd_stat.st_ino) {
175 strlcpy(cwd, pwd, PATH_MAX);
178 return cwd;
182 * Use this to get an absolute path from a relative one. If you want
183 * to resolve links, you should use real_path.
185 * If the path is already absolute, then return path. As the user is
186 * never meant to free the return value, we're safe.
188 const char *absolute_path(const char *path)
190 static char buf[PATH_MAX + 1];
192 if (!*path) {
193 die("The empty string is not a valid path");
194 } else if (is_absolute_path(path)) {
195 if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
196 die("Too long path: %.*s", 60, path);
197 } else {
198 size_t len;
199 const char *fmt;
200 const char *cwd = get_pwd_cwd();
201 if (!cwd)
202 die_errno("Cannot determine the current working directory");
203 len = strlen(cwd);
204 fmt = (len > 0 && is_dir_sep(cwd[len-1])) ? "%s%s" : "%s/%s";
205 if (snprintf(buf, PATH_MAX, fmt, cwd, path) >= PATH_MAX)
206 die("Too long path: %.*s", 60, path);
208 return buf;
212 * Unlike prefix_path, this should be used if the named file does
213 * not have to interact with index entry; i.e. name of a random file
214 * on the filesystem.
216 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
218 static char path[PATH_MAX];
219 #ifndef WIN32
220 if (!pfx_len || is_absolute_path(arg))
221 return arg;
222 memcpy(path, pfx, pfx_len);
223 strcpy(path + pfx_len, arg);
224 #else
225 char *p;
226 /* don't add prefix to absolute paths, but still replace '\' by '/' */
227 if (is_absolute_path(arg))
228 pfx_len = 0;
229 else if (pfx_len)
230 memcpy(path, pfx, pfx_len);
231 strcpy(path + pfx_len, arg);
232 for (p = path + pfx_len; *p; p++)
233 if (*p == '\\')
234 *p = '/';
235 #endif
236 return path;