freshlybakedca.ke
Git fork
1#include "git-compat-util.h"
2#include "abspath.h"
3#include "environment.h"
4#include "exec-cmd.h"
5#include "gettext.h"
6#include "path.h"
7#include "run-command.h"
8#include "strvec.h"
9#include "trace.h"
10#include "trace2.h"
11
12#if defined(RUNTIME_PREFIX)
13
14#if defined(HAVE_NS_GET_EXECUTABLE_PATH)
15#include <mach-o/dyld.h>
16#endif
17
18#if defined(HAVE_BSD_KERN_PROC_SYSCTL)
19#include <sys/param.h>
20#include <sys/types.h>
21#include <sys/sysctl.h>
22#endif
23
24#endif /* RUNTIME_PREFIX */
25
26#define MAX_ARGS 32
27
28static const char *system_prefix(void);
29
30#ifdef RUNTIME_PREFIX
31
32/**
33 * When using a runtime prefix, Git dynamically resolves paths relative to its
34 * executable.
35 *
36 * The method for determining the path of the executable is highly
37 * platform-specific.
38 */
39
40/**
41 * Path to the current Git executable. Resolved on startup by
42 * 'git_resolve_executable_dir'.
43 */
44static const char *executable_dirname;
45
46static const char *system_prefix(void)
47{
48 static const char *prefix;
49
50 assert(executable_dirname);
51 assert(is_absolute_path(executable_dirname));
52
53 if (!prefix &&
54 !(prefix = strip_path_suffix(executable_dirname, GIT_EXEC_PATH)) &&
55 !(prefix = strip_path_suffix(executable_dirname, BINDIR)) &&
56 !(prefix = strip_path_suffix(executable_dirname, "git"))) {
57 prefix = FALLBACK_RUNTIME_PREFIX;
58 trace_printf("RUNTIME_PREFIX requested, "
59 "but prefix computation failed. "
60 "Using static fallback '%s'.\n", prefix);
61 }
62 return prefix;
63}
64
65/*
66 * Resolves the executable path from argv[0], only if it is absolute.
67 *
68 * Returns 0 on success, -1 on failure.
69 */
70static int git_get_exec_path_from_argv0(struct strbuf *buf, const char *argv0)
71{
72 const char *slash;
73
74 if (!argv0 || !*argv0)
75 return -1;
76
77 slash = find_last_dir_sep(argv0);
78 if (slash) {
79 trace_printf("trace: resolved executable path from argv0: %s\n",
80 argv0);
81 strbuf_add_absolute_path(buf, argv0);
82 return 0;
83 }
84 return -1;
85}
86
87#ifdef PROCFS_EXECUTABLE_PATH
88/*
89 * Resolves the executable path by examining a procfs symlink.
90 *
91 * Returns 0 on success, -1 on failure.
92 */
93static int git_get_exec_path_procfs(struct strbuf *buf)
94{
95 if (strbuf_realpath(buf, PROCFS_EXECUTABLE_PATH, 0)) {
96 trace_printf(
97 "trace: resolved executable path from procfs: %s\n",
98 buf->buf);
99 return 0;
100 }
101 return -1;
102}
103#endif /* PROCFS_EXECUTABLE_PATH */
104
105#ifdef HAVE_BSD_KERN_PROC_SYSCTL
106/*
107 * Resolves the executable path using KERN_PROC_PATHNAME BSD sysctl.
108 *
109 * Returns 0 on success, -1 on failure.
110 */
111static int git_get_exec_path_bsd_sysctl(struct strbuf *buf)
112{
113 int mib[4];
114 char path[MAXPATHLEN];
115 size_t cb = sizeof(path);
116
117 mib[0] = CTL_KERN;
118 mib[1] = KERN_PROC;
119 mib[2] = KERN_PROC_PATHNAME;
120 mib[3] = -1;
121 if (!sysctl(mib, 4, path, &cb, NULL, 0)) {
122 trace_printf(
123 "trace: resolved executable path from sysctl: %s\n",
124 path);
125 strbuf_addstr(buf, path);
126 return 0;
127 }
128 return -1;
129}
130#endif /* HAVE_BSD_KERN_PROC_SYSCTL */
131
132#ifdef HAVE_NS_GET_EXECUTABLE_PATH
133/*
134 * Resolves the executable path by querying Darwin application stack.
135 *
136 * Returns 0 on success, -1 on failure.
137 */
138static int git_get_exec_path_darwin(struct strbuf *buf)
139{
140 char path[PATH_MAX];
141 uint32_t size = sizeof(path);
142 if (!_NSGetExecutablePath(path, &size)) {
143 trace_printf(
144 "trace: resolved executable path from Darwin stack: %s\n",
145 path);
146 strbuf_addstr(buf, path);
147 return 0;
148 }
149 return -1;
150}
151#endif /* HAVE_NS_GET_EXECUTABLE_PATH */
152
153#ifdef HAVE_ZOS_GET_EXECUTABLE_PATH
154/*
155 * Resolves the executable path from current program's directory and name.
156 *
157 * Returns 0 on success, -1 on failure.
158 */
159static int git_get_exec_path_zos(struct strbuf *buf)
160{
161 char *dir = __getprogramdir();
162 char *exe = getprogname();
163 if (dir && exe) {
164 strbuf_addf(buf, "%s/%s", dir, exe);
165 return 0;
166 }
167 return -1;
168}
169
170#endif /* HAVE_ZOS_GET_EXECUTABLE_PATH */
171
172#ifdef HAVE_WPGMPTR
173/*
174 * Resolves the executable path by using the global variable _wpgmptr.
175 *
176 * Returns 0 on success, -1 on failure.
177 */
178static int git_get_exec_path_wpgmptr(struct strbuf *buf)
179{
180 int len = wcslen(_wpgmptr) * 3 + 1;
181 strbuf_grow(buf, len);
182 len = xwcstoutf(buf->buf, _wpgmptr, len);
183 if (len < 0)
184 return -1;
185 buf->len += len;
186 return 0;
187}
188#endif /* HAVE_WPGMPTR */
189
190/*
191 * Resolves the absolute path of the current executable.
192 *
193 * Returns 0 on success, -1 on failure.
194 */
195static int git_get_exec_path(struct strbuf *buf, const char *argv0)
196{
197 /*
198 * Identifying the executable path is operating system specific.
199 * Selectively employ all available methods in order of preference,
200 * preferring highly-available authoritative methods over
201 * selectively-available or non-authoritative methods.
202 *
203 * All cases fall back on resolving against argv[0] if there isn't a
204 * better functional method. However, note that argv[0] can be
205 * used-supplied on many operating systems, and is not authoritative
206 * in those cases.
207 *
208 * Each of these functions returns 0 on success, so evaluation will stop
209 * after the first successful method.
210 */
211 if (
212#ifdef HAVE_BSD_KERN_PROC_SYSCTL
213 git_get_exec_path_bsd_sysctl(buf) &&
214#endif /* HAVE_BSD_KERN_PROC_SYSCTL */
215
216#ifdef HAVE_NS_GET_EXECUTABLE_PATH
217 git_get_exec_path_darwin(buf) &&
218#endif /* HAVE_NS_GET_EXECUTABLE_PATH */
219
220#ifdef PROCFS_EXECUTABLE_PATH
221 git_get_exec_path_procfs(buf) &&
222#endif /* PROCFS_EXECUTABLE_PATH */
223
224#ifdef HAVE_WPGMPTR
225 git_get_exec_path_wpgmptr(buf) &&
226#endif /* HAVE_WPGMPTR */
227
228#ifdef HAVE_ZOS_GET_EXECUTABLE_PATH
229 git_get_exec_path_zos(buf) &&
230#endif /*HAVE_ZOS_GET_EXECUTABLE_PATH */
231
232 git_get_exec_path_from_argv0(buf, argv0)) {
233 return -1;
234 }
235
236 if (strbuf_normalize_path(buf)) {
237 trace_printf("trace: could not normalize path: %s\n", buf->buf);
238 return -1;
239 }
240
241 trace2_cmd_path(buf->buf);
242
243 return 0;
244}
245
246void git_resolve_executable_dir(const char *argv0)
247{
248 struct strbuf buf = STRBUF_INIT;
249 char *resolved;
250 const char *slash;
251
252 if (git_get_exec_path(&buf, argv0)) {
253 trace_printf(
254 "trace: could not determine executable path from: %s\n",
255 argv0);
256 strbuf_release(&buf);
257 return;
258 }
259
260 resolved = strbuf_detach(&buf, NULL);
261 slash = find_last_dir_sep(resolved);
262 if (slash)
263 resolved[slash - resolved] = '\0';
264
265 executable_dirname = resolved;
266 trace_printf("trace: resolved executable dir: %s\n",
267 executable_dirname);
268}
269
270#else
271
272/*
273 * When not using a runtime prefix, Git uses a hard-coded path.
274 */
275static const char *system_prefix(void)
276{
277 return FALLBACK_RUNTIME_PREFIX;
278}
279
280/*
281 * This is called during initialization, but No work needs to be done here when
282 * runtime prefix is not being used.
283 */
284void git_resolve_executable_dir(const char *argv0 UNUSED)
285{
286}
287
288#endif /* RUNTIME_PREFIX */
289
290char *system_path(const char *path)
291{
292 struct strbuf d = STRBUF_INIT;
293
294 if (is_absolute_path(path))
295 return xstrdup(path);
296
297 strbuf_addf(&d, "%s/%s", system_prefix(), path);
298 return strbuf_detach(&d, NULL);
299}
300
301static const char *exec_path_value;
302
303void git_set_exec_path(const char *exec_path)
304{
305 exec_path_value = exec_path;
306 /*
307 * Propagate this setting to external programs.
308 */
309 setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
310}
311
312/* Returns the highest-priority location to look for git programs. */
313const char *git_exec_path(void)
314{
315 if (!exec_path_value) {
316 const char *env = getenv(EXEC_PATH_ENVIRONMENT);
317 if (env && *env)
318 exec_path_value = xstrdup(env);
319 else
320 exec_path_value = system_path(GIT_EXEC_PATH);
321 }
322 return exec_path_value;
323}
324
325static void add_path(struct strbuf *out, const char *path)
326{
327 if (path && *path) {
328 strbuf_add_absolute_path(out, path);
329 strbuf_addch(out, PATH_SEP);
330 }
331}
332
333void setup_path(void)
334{
335 const char *exec_path = git_exec_path();
336 const char *old_path = getenv("PATH");
337 struct strbuf new_path = STRBUF_INIT;
338
339 git_set_exec_path(exec_path);
340 add_path(&new_path, exec_path);
341
342 if (old_path)
343 strbuf_addstr(&new_path, old_path);
344 else
345 strbuf_addstr(&new_path, _PATH_DEFPATH);
346
347 setenv("PATH", new_path.buf, 1);
348
349 strbuf_release(&new_path);
350}
351
352const char **prepare_git_cmd(struct strvec *out, const char **argv)
353{
354 strvec_push(out, "git");
355 strvec_pushv(out, argv);
356 return out->v;
357}
358
359int execv_git_cmd(const char **argv)
360{
361 struct strvec nargv = STRVEC_INIT;
362
363 prepare_git_cmd(&nargv, argv);
364 trace_argv_printf(nargv.v, "trace: exec:");
365
366 /* execvp() can only ever return if it fails */
367 sane_execvp("git", (char **)nargv.v);
368
369 trace_printf("trace: exec failed: %s\n", strerror(errno));
370
371 strvec_clear(&nargv);
372 return -1;
373}
374
375int execl_git_cmd(const char *cmd, ...)
376{
377 int argc;
378 const char *argv[MAX_ARGS + 1];
379 const char *arg;
380 va_list param;
381
382 va_start(param, cmd);
383 argv[0] = cmd;
384 argc = 1;
385 while (argc < MAX_ARGS) {
386 arg = argv[argc++] = va_arg(param, char *);
387 if (!arg)
388 break;
389 }
390 va_end(param);
391 if (MAX_ARGS <= argc)
392 return error(_("too many args to run %s"), cmd);
393
394 argv[argc] = NULL;
395 return execv_git_cmd(argv);
396}