user-manual.txt: add missing section label
[git/git.git] / exec-cmd.c
CommitLineData
77cb17e9 1#include "cache.h"
d807c4a0 2#include "exec-cmd.h"
575ba9d6 3#include "quote.h"
20574f55 4#include "argv-array.h"
77cb17e9 5
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6#if defined(RUNTIME_PREFIX)
7
8#if defined(HAVE_NS_GET_EXECUTABLE_PATH)
9#include <mach-o/dyld.h>
10#endif
11
12#if defined(HAVE_BSD_KERN_PROC_SYSCTL)
13#include <sys/param.h>
14#include <sys/types.h>
15#include <sys/sysctl.h>
16#endif
17
18#endif /* RUNTIME_PREFIX */
19
20#define MAX_ARGS 32
21
22static const char *system_prefix(void);
77cb17e9 23
35fb0e86 24#ifdef RUNTIME_PREFIX
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25
26/**
27 * When using a runtime prefix, Git dynamically resolves paths relative to its
28 * executable.
29 *
30 * The method for determining the path of the executable is highly
31 * platform-specific.
32 */
33
34/**
35 * Path to the current Git executable. Resolved on startup by
36 * 'git_resolve_executable_dir'.
37 */
38static const char *executable_dirname;
026fa0d5 39
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40static const char *system_prefix(void)
41{
42 static const char *prefix;
026fa0d5 43
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44 assert(executable_dirname);
45 assert(is_absolute_path(executable_dirname));
35fb0e86 46
024aa7d8 47 if (!prefix &&
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48 !(prefix = strip_path_suffix(executable_dirname, GIT_EXEC_PATH)) &&
49 !(prefix = strip_path_suffix(executable_dirname, BINDIR)) &&
50 !(prefix = strip_path_suffix(executable_dirname, "git"))) {
4d5b4c24 51 prefix = FALLBACK_RUNTIME_PREFIX;
aa094570 52 trace_printf("RUNTIME_PREFIX requested, "
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53 "but prefix computation failed. "
54 "Using static fallback '%s'.\n", prefix);
55 }
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56 return prefix;
57}
c1bb33c9 58
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59/*
60 * Resolves the executable path from argv[0], only if it is absolute.
61 *
62 * Returns 0 on success, -1 on failure.
63 */
64static int git_get_exec_path_from_argv0(struct strbuf *buf, const char *argv0)
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65{
66 const char *slash;
67
68 if (!argv0 || !*argv0)
226c0ddd 69 return -1;
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70
71 slash = find_last_dir_sep(argv0);
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72 if (slash) {
73 trace_printf("trace: resolved executable path from argv0: %s\n",
74 argv0);
75 strbuf_add_absolute_path(buf, argv0);
76 return 0;
77 }
78 return -1;
79}
c1bb33c9 80
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81#ifdef PROCFS_EXECUTABLE_PATH
82/*
83 * Resolves the executable path by examining a procfs symlink.
84 *
85 * Returns 0 on success, -1 on failure.
86 */
87static int git_get_exec_path_procfs(struct strbuf *buf)
88{
89 if (strbuf_realpath(buf, PROCFS_EXECUTABLE_PATH, 0)) {
90 trace_printf(
91 "trace: resolved executable path from procfs: %s\n",
92 buf->buf);
93 return 0;
94 }
95 return -1;
96}
97#endif /* PROCFS_EXECUTABLE_PATH */
98
99#ifdef HAVE_BSD_KERN_PROC_SYSCTL
100/*
101 * Resolves the executable path using KERN_PROC_PATHNAME BSD sysctl.
102 *
103 * Returns 0 on success, -1 on failure.
104 */
105static int git_get_exec_path_bsd_sysctl(struct strbuf *buf)
106{
107 int mib[4];
108 char path[MAXPATHLEN];
109 size_t cb = sizeof(path);
110
111 mib[0] = CTL_KERN;
112 mib[1] = KERN_PROC;
113 mib[2] = KERN_PROC_PATHNAME;
114 mib[3] = -1;
115 if (!sysctl(mib, 4, path, &cb, NULL, 0)) {
116 trace_printf(
117 "trace: resolved executable path from sysctl: %s\n",
118 path);
119 strbuf_addstr(buf, path);
120 return 0;
121 }
122 return -1;
123}
124#endif /* HAVE_BSD_KERN_PROC_SYSCTL */
125
126#ifdef HAVE_NS_GET_EXECUTABLE_PATH
127/*
128 * Resolves the executable path by querying Darwin application stack.
129 *
130 * Returns 0 on success, -1 on failure.
131 */
132static int git_get_exec_path_darwin(struct strbuf *buf)
133{
134 char path[PATH_MAX];
135 uint32_t size = sizeof(path);
136 if (!_NSGetExecutablePath(path, &size)) {
137 trace_printf(
138 "trace: resolved executable path from Darwin stack: %s\n",
139 path);
140 strbuf_addstr(buf, path);
141 return 0;
142 }
143 return -1;
144}
145#endif /* HAVE_NS_GET_EXECUTABLE_PATH */
146
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147#ifdef HAVE_WPGMPTR
148/*
149 * Resolves the executable path by using the global variable _wpgmptr.
150 *
151 * Returns 0 on success, -1 on failure.
152 */
153static int git_get_exec_path_wpgmptr(struct strbuf *buf)
154{
155 int len = wcslen(_wpgmptr) * 3 + 1;
156 strbuf_grow(buf, len);
157 len = xwcstoutf(buf->buf, _wpgmptr, len);
158 if (len < 0)
159 return -1;
160 buf->len += len;
161 return 0;
162}
163#endif /* HAVE_WPGMPTR */
164
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165/*
166 * Resolves the absolute path of the current executable.
167 *
168 * Returns 0 on success, -1 on failure.
169 */
170static int git_get_exec_path(struct strbuf *buf, const char *argv0)
171{
172 /*
173 * Identifying the executable path is operating system specific.
174 * Selectively employ all available methods in order of preference,
175 * preferring highly-available authoritative methods over
176 * selectively-available or non-authoritative methods.
177 *
178 * All cases fall back on resolving against argv[0] if there isn't a
179 * better functional method. However, note that argv[0] can be
180 * used-supplied on many operating systems, and is not authoritative
181 * in those cases.
182 *
183 * Each of these functions returns 0 on success, so evaluation will stop
184 * after the first successful method.
185 */
186 if (
187#ifdef HAVE_BSD_KERN_PROC_SYSCTL
188 git_get_exec_path_bsd_sysctl(buf) &&
189#endif /* HAVE_BSD_KERN_PROC_SYSCTL */
190
191#ifdef HAVE_NS_GET_EXECUTABLE_PATH
192 git_get_exec_path_darwin(buf) &&
193#endif /* HAVE_NS_GET_EXECUTABLE_PATH */
194
195#ifdef PROCFS_EXECUTABLE_PATH
196 git_get_exec_path_procfs(buf) &&
197#endif /* PROCFS_EXECUTABLE_PATH */
198
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199#ifdef HAVE_WPGMPTR
200 git_get_exec_path_wpgmptr(buf) &&
201#endif /* HAVE_WPGMPTR */
202
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203 git_get_exec_path_from_argv0(buf, argv0)) {
204 return -1;
205 }
206
207 if (strbuf_normalize_path(buf)) {
208 trace_printf("trace: could not normalize path: %s\n", buf->buf);
209 return -1;
210 }
211
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212 trace2_cmd_path(buf->buf);
213
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214 return 0;
215}
c1bb33c9 216
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217void git_resolve_executable_dir(const char *argv0)
218{
219 struct strbuf buf = STRBUF_INIT;
220 char *resolved;
221 const char *slash;
222
223 if (git_get_exec_path(&buf, argv0)) {
224 trace_printf(
225 "trace: could not determine executable path from: %s\n",
226 argv0);
227 strbuf_release(&buf);
228 return;
229 }
230
231 resolved = strbuf_detach(&buf, NULL);
232 slash = find_last_dir_sep(resolved);
c1bb33c9 233 if (slash)
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234 resolved[slash - resolved] = '\0';
235
236 executable_dirname = resolved;
237 trace_printf("trace: resolved executable dir: %s\n",
238 executable_dirname);
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239}
240
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241#else
242
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243/*
244 * When not using a runtime prefix, Git uses a hard-coded path.
245 */
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246static const char *system_prefix(void)
247{
4d5b4c24 248 return FALLBACK_RUNTIME_PREFIX;
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249}
250
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251/*
252 * This is called during initialization, but No work needs to be done here when
253 * runtime prefix is not being used.
254 */
255void git_resolve_executable_dir(const char *argv0)
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256{
257}
258
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259#endif /* RUNTIME_PREFIX */
260
261char *system_path(const char *path)
262{
263 struct strbuf d = STRBUF_INIT;
264
265 if (is_absolute_path(path))
266 return xstrdup(path);
35fb0e86 267
39b2f6af 268 strbuf_addf(&d, "%s/%s", system_prefix(), path);
59362e56 269 return strbuf_detach(&d, NULL);
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270}
271
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272static const char *exec_path_value;
273
274void git_set_exec_path(const char *exec_path)
77cb17e9 275{
226c0ddd 276 exec_path_value = exec_path;
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277 /*
278 * Propagate this setting to external programs.
279 */
280 setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
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281}
282
226c0ddd 283/* Returns the highest-priority location to look for git programs. */
962554c6 284const char *git_exec_path(void)
77cb17e9 285{
226c0ddd 286 if (!exec_path_value) {
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287 const char *env = getenv(EXEC_PATH_ENVIRONMENT);
288 if (env && *env)
226c0ddd 289 exec_path_value = xstrdup(env);
007ac544 290 else
226c0ddd 291 exec_path_value = system_path(GIT_EXEC_PATH);
77cb17e9 292 }
226c0ddd 293 return exec_path_value;
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294}
295
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296static void add_path(struct strbuf *out, const char *path)
297{
298 if (path && *path) {
9610decf 299 strbuf_add_absolute_path(out, path);
80ba074f 300 strbuf_addch(out, PATH_SEP);
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301 }
302}
303
e1464ca7 304void setup_path(void)
511707d4 305{
226c0ddd 306 const char *exec_path = git_exec_path();
511707d4 307 const char *old_path = getenv("PATH");
f285a2d7 308 struct strbuf new_path = STRBUF_INIT;
511707d4 309
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310 git_set_exec_path(exec_path);
311 add_path(&new_path, exec_path);
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312
313 if (old_path)
314 strbuf_addstr(&new_path, old_path);
315 else
cb6a22c0 316 strbuf_addstr(&new_path, _PATH_DEFPATH);
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317
318 setenv("PATH", new_path.buf, 1);
319
320 strbuf_release(&new_path);
321}
77cb17e9 322
20574f55 323const char **prepare_git_cmd(struct argv_array *out, const char **argv)
77cb17e9 324{
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325 argv_array_push(out, "git");
326 argv_array_pushv(out, argv);
327 return out->argv;
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328}
329
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330int execv_git_cmd(const char **argv)
331{
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332 struct argv_array nargv = ARGV_ARRAY_INIT;
333
334 prepare_git_cmd(&nargv, argv);
335 trace_argv_printf(nargv.argv, "trace: exec:");
575ba9d6 336
511707d4 337 /* execvp() can only ever return if it fails */
20574f55 338 sane_execvp("git", (char **)nargv.argv);
77cb17e9 339
511707d4 340 trace_printf("trace: exec failed: %s\n", strerror(errno));
575ba9d6 341
20574f55 342 argv_array_clear(&nargv);
511707d4 343 return -1;
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344}
345
226c0ddd 346int execl_git_cmd(const char *cmd, ...)
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347{
348 int argc;
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349 const char *argv[MAX_ARGS + 1];
350 const char *arg;
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351 va_list param;
352
353 va_start(param, cmd);
354 argv[0] = cmd;
355 argc = 1;
356 while (argc < MAX_ARGS) {
357 arg = argv[argc++] = va_arg(param, char *);
358 if (!arg)
359 break;
360 }
361 va_end(param);
362 if (MAX_ARGS <= argc)
31a55e91 363 return error(_("too many args to run %s"), cmd);
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364
365 argv[argc] = NULL;
366 return execv_git_cmd(argv);
367}