git/exec-cmd.c
Elijah Newren d1cbe1e6d8 hash-ll.h: split out of hash.h to remove dependency on repository.h
hash.h depends upon and includes repository.h, due to the definition and
use of the_hash_algo (defined as the_repository->hash_algo).  However,
most headers trying to include hash.h are only interested in the layout
of the structs like object_id.  Move the parts of hash.h that do not
depend upon repository.h into a new file hash-ll.h (the "low level"
parts of hash.h), and adjust other files to use this new header where
the convenience inline functions aren't needed.

This allows hash.h and object.h to be fairly small, minimal headers.  It
also exposes a lot of hidden dependencies on both path.h (which was
brought in by repository.h) and repository.h (which was previously
implicitly brought in by object.h), so also adjust other files to be
more explicit about what they depend upon.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-24 12:47:32 -07:00

374 lines
8.1 KiB
C

#include "cache.h"
#include "abspath.h"
#include "environment.h"
#include "exec-cmd.h"
#include "gettext.h"
#include "path.h"
#include "quote.h"
#include "strvec.h"
#include "trace.h"
#include "trace2.h"
#if defined(RUNTIME_PREFIX)
#if defined(HAVE_NS_GET_EXECUTABLE_PATH)
#include <mach-o/dyld.h>
#endif
#if defined(HAVE_BSD_KERN_PROC_SYSCTL)
#include <sys/param.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#endif
#endif /* RUNTIME_PREFIX */
#define MAX_ARGS 32
static const char *system_prefix(void);
#ifdef RUNTIME_PREFIX
/**
* When using a runtime prefix, Git dynamically resolves paths relative to its
* executable.
*
* The method for determining the path of the executable is highly
* platform-specific.
*/
/**
* Path to the current Git executable. Resolved on startup by
* 'git_resolve_executable_dir'.
*/
static const char *executable_dirname;
static const char *system_prefix(void)
{
static const char *prefix;
assert(executable_dirname);
assert(is_absolute_path(executable_dirname));
if (!prefix &&
!(prefix = strip_path_suffix(executable_dirname, GIT_EXEC_PATH)) &&
!(prefix = strip_path_suffix(executable_dirname, BINDIR)) &&
!(prefix = strip_path_suffix(executable_dirname, "git"))) {
prefix = FALLBACK_RUNTIME_PREFIX;
trace_printf("RUNTIME_PREFIX requested, "
"but prefix computation failed. "
"Using static fallback '%s'.\n", prefix);
}
return prefix;
}
/*
* Resolves the executable path from argv[0], only if it is absolute.
*
* Returns 0 on success, -1 on failure.
*/
static int git_get_exec_path_from_argv0(struct strbuf *buf, const char *argv0)
{
const char *slash;
if (!argv0 || !*argv0)
return -1;
slash = find_last_dir_sep(argv0);
if (slash) {
trace_printf("trace: resolved executable path from argv0: %s\n",
argv0);
strbuf_add_absolute_path(buf, argv0);
return 0;
}
return -1;
}
#ifdef PROCFS_EXECUTABLE_PATH
/*
* Resolves the executable path by examining a procfs symlink.
*
* Returns 0 on success, -1 on failure.
*/
static int git_get_exec_path_procfs(struct strbuf *buf)
{
if (strbuf_realpath(buf, PROCFS_EXECUTABLE_PATH, 0)) {
trace_printf(
"trace: resolved executable path from procfs: %s\n",
buf->buf);
return 0;
}
return -1;
}
#endif /* PROCFS_EXECUTABLE_PATH */
#ifdef HAVE_BSD_KERN_PROC_SYSCTL
/*
* Resolves the executable path using KERN_PROC_PATHNAME BSD sysctl.
*
* Returns 0 on success, -1 on failure.
*/
static int git_get_exec_path_bsd_sysctl(struct strbuf *buf)
{
int mib[4];
char path[MAXPATHLEN];
size_t cb = sizeof(path);
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_PATHNAME;
mib[3] = -1;
if (!sysctl(mib, 4, path, &cb, NULL, 0)) {
trace_printf(
"trace: resolved executable path from sysctl: %s\n",
path);
strbuf_addstr(buf, path);
return 0;
}
return -1;
}
#endif /* HAVE_BSD_KERN_PROC_SYSCTL */
#ifdef HAVE_NS_GET_EXECUTABLE_PATH
/*
* Resolves the executable path by querying Darwin application stack.
*
* Returns 0 on success, -1 on failure.
*/
static int git_get_exec_path_darwin(struct strbuf *buf)
{
char path[PATH_MAX];
uint32_t size = sizeof(path);
if (!_NSGetExecutablePath(path, &size)) {
trace_printf(
"trace: resolved executable path from Darwin stack: %s\n",
path);
strbuf_addstr(buf, path);
return 0;
}
return -1;
}
#endif /* HAVE_NS_GET_EXECUTABLE_PATH */
#ifdef HAVE_WPGMPTR
/*
* Resolves the executable path by using the global variable _wpgmptr.
*
* Returns 0 on success, -1 on failure.
*/
static int git_get_exec_path_wpgmptr(struct strbuf *buf)
{
int len = wcslen(_wpgmptr) * 3 + 1;
strbuf_grow(buf, len);
len = xwcstoutf(buf->buf, _wpgmptr, len);
if (len < 0)
return -1;
buf->len += len;
return 0;
}
#endif /* HAVE_WPGMPTR */
/*
* Resolves the absolute path of the current executable.
*
* Returns 0 on success, -1 on failure.
*/
static int git_get_exec_path(struct strbuf *buf, const char *argv0)
{
/*
* Identifying the executable path is operating system specific.
* Selectively employ all available methods in order of preference,
* preferring highly-available authoritative methods over
* selectively-available or non-authoritative methods.
*
* All cases fall back on resolving against argv[0] if there isn't a
* better functional method. However, note that argv[0] can be
* used-supplied on many operating systems, and is not authoritative
* in those cases.
*
* Each of these functions returns 0 on success, so evaluation will stop
* after the first successful method.
*/
if (
#ifdef HAVE_BSD_KERN_PROC_SYSCTL
git_get_exec_path_bsd_sysctl(buf) &&
#endif /* HAVE_BSD_KERN_PROC_SYSCTL */
#ifdef HAVE_NS_GET_EXECUTABLE_PATH
git_get_exec_path_darwin(buf) &&
#endif /* HAVE_NS_GET_EXECUTABLE_PATH */
#ifdef PROCFS_EXECUTABLE_PATH
git_get_exec_path_procfs(buf) &&
#endif /* PROCFS_EXECUTABLE_PATH */
#ifdef HAVE_WPGMPTR
git_get_exec_path_wpgmptr(buf) &&
#endif /* HAVE_WPGMPTR */
git_get_exec_path_from_argv0(buf, argv0)) {
return -1;
}
if (strbuf_normalize_path(buf)) {
trace_printf("trace: could not normalize path: %s\n", buf->buf);
return -1;
}
trace2_cmd_path(buf->buf);
return 0;
}
void git_resolve_executable_dir(const char *argv0)
{
struct strbuf buf = STRBUF_INIT;
char *resolved;
const char *slash;
if (git_get_exec_path(&buf, argv0)) {
trace_printf(
"trace: could not determine executable path from: %s\n",
argv0);
strbuf_release(&buf);
return;
}
resolved = strbuf_detach(&buf, NULL);
slash = find_last_dir_sep(resolved);
if (slash)
resolved[slash - resolved] = '\0';
executable_dirname = resolved;
trace_printf("trace: resolved executable dir: %s\n",
executable_dirname);
}
#else
/*
* When not using a runtime prefix, Git uses a hard-coded path.
*/
static const char *system_prefix(void)
{
return FALLBACK_RUNTIME_PREFIX;
}
/*
* This is called during initialization, but No work needs to be done here when
* runtime prefix is not being used.
*/
void git_resolve_executable_dir(const char *argv0 UNUSED)
{
}
#endif /* RUNTIME_PREFIX */
char *system_path(const char *path)
{
struct strbuf d = STRBUF_INIT;
if (is_absolute_path(path))
return xstrdup(path);
strbuf_addf(&d, "%s/%s", system_prefix(), path);
return strbuf_detach(&d, NULL);
}
static const char *exec_path_value;
void git_set_exec_path(const char *exec_path)
{
exec_path_value = exec_path;
/*
* Propagate this setting to external programs.
*/
setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
}
/* Returns the highest-priority location to look for git programs. */
const char *git_exec_path(void)
{
if (!exec_path_value) {
const char *env = getenv(EXEC_PATH_ENVIRONMENT);
if (env && *env)
exec_path_value = xstrdup(env);
else
exec_path_value = system_path(GIT_EXEC_PATH);
}
return exec_path_value;
}
static void add_path(struct strbuf *out, const char *path)
{
if (path && *path) {
strbuf_add_absolute_path(out, path);
strbuf_addch(out, PATH_SEP);
}
}
void setup_path(void)
{
const char *exec_path = git_exec_path();
const char *old_path = getenv("PATH");
struct strbuf new_path = STRBUF_INIT;
git_set_exec_path(exec_path);
add_path(&new_path, exec_path);
if (old_path)
strbuf_addstr(&new_path, old_path);
else
strbuf_addstr(&new_path, _PATH_DEFPATH);
setenv("PATH", new_path.buf, 1);
strbuf_release(&new_path);
}
const char **prepare_git_cmd(struct strvec *out, const char **argv)
{
strvec_push(out, "git");
strvec_pushv(out, argv);
return out->v;
}
int execv_git_cmd(const char **argv)
{
struct strvec nargv = STRVEC_INIT;
prepare_git_cmd(&nargv, argv);
trace_argv_printf(nargv.v, "trace: exec:");
/* execvp() can only ever return if it fails */
sane_execvp("git", (char **)nargv.v);
trace_printf("trace: exec failed: %s\n", strerror(errno));
strvec_clear(&nargv);
return -1;
}
int execl_git_cmd(const char *cmd, ...)
{
int argc;
const char *argv[MAX_ARGS + 1];
const char *arg;
va_list param;
va_start(param, cmd);
argv[0] = cmd;
argc = 1;
while (argc < MAX_ARGS) {
arg = argv[argc++] = va_arg(param, char *);
if (!arg)
break;
}
va_end(param);
if (MAX_ARGS <= argc)
return error(_("too many args to run %s"), cmd);
argv[argc] = NULL;
return execv_git_cmd(argv);
}