linux-stable-rt/Documentation/perf_counter/util/exec_cmd.c

166 lines
3.2 KiB
C

#include "cache.h"
#include "exec_cmd.h"
#include "quote.h"
#define MAX_ARGS 32
extern char **environ;
static const char *argv_exec_path;
static const char *argv0_path;
const char *system_path(const char *path)
{
#ifdef RUNTIME_PREFIX
static const char *prefix;
#else
static const char *prefix = PREFIX;
#endif
struct strbuf d = STRBUF_INIT;
if (is_absolute_path(path))
return path;
#ifdef RUNTIME_PREFIX
assert(argv0_path);
assert(is_absolute_path(argv0_path));
if (!prefix &&
!(prefix = strip_path_suffix(argv0_path, PERF_EXEC_PATH)) &&
!(prefix = strip_path_suffix(argv0_path, BINDIR)) &&
!(prefix = strip_path_suffix(argv0_path, "perf"))) {
prefix = PREFIX;
fprintf(stderr, "RUNTIME_PREFIX requested, "
"but prefix computation failed. "
"Using static fallback '%s'.\n", prefix);
}
#endif
strbuf_addf(&d, "%s/%s", prefix, path);
path = strbuf_detach(&d, NULL);
return path;
}
const char *perf_extract_argv0_path(const char *argv0)
{
const char *slash;
if (!argv0 || !*argv0)
return NULL;
slash = argv0 + strlen(argv0);
while (argv0 <= slash && !is_dir_sep(*slash))
slash--;
if (slash >= argv0) {
argv0_path = strndup(argv0, slash - argv0);
return slash + 1;
}
return argv0;
}
void perf_set_argv_exec_path(const char *exec_path)
{
argv_exec_path = exec_path;
/*
* Propagate this setting to external programs.
*/
setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
}
/* Returns the highest-priority, location to look for perf programs. */
const char *perf_exec_path(void)
{
const char *env;
if (argv_exec_path)
return argv_exec_path;
env = getenv(EXEC_PATH_ENVIRONMENT);
if (env && *env) {
return env;
}
return system_path(PERF_EXEC_PATH);
}
static void add_path(struct strbuf *out, const char *path)
{
if (path && *path) {
if (is_absolute_path(path))
strbuf_addstr(out, path);
else
strbuf_addstr(out, make_nonrelative_path(path));
strbuf_addch(out, PATH_SEP);
}
}
void setup_path(void)
{
const char *old_path = getenv("PATH");
struct strbuf new_path = STRBUF_INIT;
add_path(&new_path, perf_exec_path());
add_path(&new_path, argv0_path);
if (old_path)
strbuf_addstr(&new_path, old_path);
else
strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
setenv("PATH", new_path.buf, 1);
strbuf_release(&new_path);
}
const char **prepare_perf_cmd(const char **argv)
{
int argc;
const char **nargv;
for (argc = 0; argv[argc]; argc++)
; /* just counting */
nargv = malloc(sizeof(*nargv) * (argc + 2));
nargv[0] = "perf";
for (argc = 0; argv[argc]; argc++)
nargv[argc + 1] = argv[argc];
nargv[argc + 1] = NULL;
return nargv;
}
int execv_perf_cmd(const char **argv) {
const char **nargv = prepare_perf_cmd(argv);
/* execvp() can only ever return if it fails */
execvp("perf", (char **)nargv);
free(nargv);
return -1;
}
int execl_perf_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_perf_cmd(argv);
}