tools/perf/util/exec_cmd.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3 #include "quote.h"
   4
   5 #include <string.h>
   6
   7 #define MAX_ARGS        32
   8
   9 static const char *argv_exec_path;
  10 static const char *argv0_path;
  11
  12 const char *system_path(const char *path)
  13 {
  14 #ifdef RUNTIME_PREFIX
  15         static const char *prefix;
  16 #else
  17         static const char *prefix = PREFIX;
  18 #endif
  19         struct strbuf d = STRBUF_INIT;
  20
  21         if (is_absolute_path(path))
  22                 return path;
  23
  24 #ifdef RUNTIME_PREFIX
  25         assert(argv0_path);
  26         assert(is_absolute_path(argv0_path));
  27
  28         if (!prefix &&
  29             !(prefix = strip_path_suffix(argv0_path, PERF_EXEC_PATH)) &&
  30             !(prefix = strip_path_suffix(argv0_path, BINDIR)) &&
  31             !(prefix = strip_path_suffix(argv0_path, "perf"))) {
  32                 prefix = PREFIX;
  33                 fprintf(stderr, "RUNTIME_PREFIX requested, "
  34                                 "but prefix computation failed.  "
  35                                 "Using static fallback '%s'.\n", prefix);
  36         }
  37 #endif
  38
  39         strbuf_addf(&d, "%s/%s", prefix, path);
  40         path = strbuf_detach(&d, NULL);
  41         return path;
  42 }
  43
  44 const char *perf_extract_argv0_path(const char *argv0)
  45 {
  46         const char *slash;
  47
  48         if (!argv0 || !*argv0)
  49                 return NULL;
  50         slash = argv0 + strlen(argv0);
  51
  52         while (argv0 <= slash && !is_dir_sep(*slash))
  53                 slash--;
  54
  55         if (slash >= argv0) {
  56                 argv0_path = strndup(argv0, slash - argv0);
  57                 return argv0_path ? slash + 1 : NULL;
  58         }
  59
  60         return argv0;
  61 }
  62
  63 void perf_set_argv_exec_path(const char *exec_path)
  64 {
  65         argv_exec_path = exec_path;
  66         /*
  67          * Propagate this setting to external programs.
  68          */
  69         setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
  70 }
  71
  72
  73 /* Returns the highest-priority, location to look for perf programs. */
  74 const char *perf_exec_path(void)
  75 {
  76         const char *env;
  77
  78         if (argv_exec_path)
  79                 return argv_exec_path;
  80
  81         env = getenv(EXEC_PATH_ENVIRONMENT);
  82         if (env && *env) {
  83                 return env;
  84         }
  85
  86         return system_path(PERF_EXEC_PATH);
  87 }
  88
  89 static void add_path(struct strbuf *out, const char *path)
  90 {
  91         if (path && *path) {
  92                 if (is_absolute_path(path))
  93                         strbuf_addstr(out, path);
  94                 else
  95                         strbuf_addstr(out, make_nonrelative_path(path));
  96
  97                 strbuf_addch(out, PATH_SEP);
  98         }
  99 }
 100
 101 void setup_path(void)
 102 {
 103         const char *old_path = getenv("PATH");
 104         struct strbuf new_path = STRBUF_INIT;
 105
 106         add_path(&new_path, perf_exec_path());
 107         add_path(&new_path, argv0_path);
 108
 109         if (old_path)
 110                 strbuf_addstr(&new_path, old_path);
 111         else
 112                 strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
 113
 114         setenv("PATH", new_path.buf, 1);
 115
 116         strbuf_release(&new_path);
 117 }
 118
 119 static const char **prepare_perf_cmd(const char **argv)
 120 {
 121         int argc;
 122         const char **nargv;
 123
 124         for (argc = 0; argv[argc]; argc++)
 125                 ; /* just counting */
 126         nargv = malloc(sizeof(*nargv) * (argc + 2));
 127
 128         nargv[0] = "perf";
 129         for (argc = 0; argv[argc]; argc++)
 130                 nargv[argc + 1] = argv[argc];
 131         nargv[argc + 1] = NULL;
 132         return nargv;
 133 }
 134
 135 int execv_perf_cmd(const char **argv) {
 136         const char **nargv = prepare_perf_cmd(argv);
 137
 138         /* execvp() can only ever return if it fails */
 139         execvp("perf", (char **)nargv);
 140
 141         free(nargv);
 142         return -1;
 143 }
 144
 145
 146 int execl_perf_cmd(const char *cmd,...)
 147 {
 148         int argc;
 149         const char *argv[MAX_ARGS + 1];
 150         const char *arg;
 151         va_list param;
 152
 153         va_start(param, cmd);
 154         argv[0] = cmd;
 155         argc = 1;
 156         while (argc < MAX_ARGS) {
 157                 arg = argv[argc++] = va_arg(param, char *);
 158                 if (!arg)
 159                         break;
 160         }
 161         va_end(param);
 162         if (MAX_ARGS <= argc)
 163                 return error("too many args to run %s", cmd);
 164
 165         argv[argc] = NULL;
 166         return execv_perf_cmd(argv);
 167 }