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 extern char **environ;
  10 static const char *argv_exec_path;
  11 static const char *argv0_path;
  12
  13 const char *system_path(const char *path)
  14 {
  15 #ifdef RUNTIME_PREFIX
  16         static const char *prefix;
  17 #else
  18         static const char *prefix = PREFIX;
  19 #endif
  20         struct strbuf d = STRBUF_INIT;
  21
  22         if (is_absolute_path(path))
  23                 return path;
  24
  25 #ifdef RUNTIME_PREFIX
  26         assert(argv0_path);
  27         assert(is_absolute_path(argv0_path));
  28
  29         if (!prefix &&
  30             !(prefix = strip_path_suffix(argv0_path, PERF_EXEC_PATH)) &&
  31             !(prefix = strip_path_suffix(argv0_path, BINDIR)) &&
  32             !(prefix = strip_path_suffix(argv0_path, "perf"))) {
  33                 prefix = PREFIX;
  34                 fprintf(stderr, "RUNTIME_PREFIX requested, "
  35                                 "but prefix computation failed.  "
  36                                 "Using static fallback '%s'.\n", prefix);
  37         }
  38 #endif
  39
  40         strbuf_addf(&d, "%s/%s", prefix, path);
  41         path = strbuf_detach(&d, NULL);
  42         return path;
  43 }
  44
  45 const char *perf_extract_argv0_path(const char *argv0)
  46 {
  47         const char *slash;
  48
  49         if (!argv0 || !*argv0)
  50                 return NULL;
  51         slash = argv0 + strlen(argv0);
  52
  53         while (argv0 <= slash && !is_dir_sep(*slash))
  54                 slash--;
  55
  56         if (slash >= argv0) {
  57                 argv0_path = xstrndup(argv0, slash - argv0);
  58                 return slash + 1;
  59         }
  60
  61         return argv0;
  62 }
  63
  64 void perf_set_argv_exec_path(const char *exec_path)
  65 {
  66         argv_exec_path = exec_path;
  67         /*
  68          * Propagate this setting to external programs.
  69          */
  70         setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
  71 }
  72
  73
  74 /* Returns the highest-priority, location to look for perf programs. */
  75 const char *perf_exec_path(void)
  76 {
  77         const char *env;
  78
  79         if (argv_exec_path)
  80                 return argv_exec_path;
  81
  82         env = getenv(EXEC_PATH_ENVIRONMENT);
  83         if (env && *env) {
  84                 return env;
  85         }
  86
  87         return system_path(PERF_EXEC_PATH);
  88 }
  89
  90 static void add_path(struct strbuf *out, const char *path)
  91 {
  92         if (path && *path) {
  93                 if (is_absolute_path(path))
  94                         strbuf_addstr(out, path);
  95                 else
  96                         strbuf_addstr(out, make_nonrelative_path(path));
  97
  98                 strbuf_addch(out, PATH_SEP);
  99         }
 100 }
 101
 102 void setup_path(void)
 103 {
 104         const char *old_path = getenv("PATH");
 105         struct strbuf new_path = STRBUF_INIT;
 106
 107         add_path(&new_path, perf_exec_path());
 108         add_path(&new_path, argv0_path);
 109
 110         if (old_path)
 111                 strbuf_addstr(&new_path, old_path);
 112         else
 113                 strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
 114
 115         setenv("PATH", new_path.buf, 1);
 116
 117         strbuf_release(&new_path);
 118 }
 119
 120 const char **prepare_perf_cmd(const char **argv)
 121 {
 122         int argc;
 123         const char **nargv;
 124
 125         for (argc = 0; argv[argc]; argc++)
 126                 ; /* just counting */
 127         nargv = malloc(sizeof(*nargv) * (argc + 2));
 128
 129         nargv[0] = "perf";
 130         for (argc = 0; argv[argc]; argc++)
 131                 nargv[argc + 1] = argv[argc];
 132         nargv[argc + 1] = NULL;
 133         return nargv;
 134 }
 135
 136 int execv_perf_cmd(const char **argv) {
 137         const char **nargv = prepare_perf_cmd(argv);
 138
 139         /* execvp() can only ever return if it fails */
 140         execvp("perf", (char **)nargv);
 141
 142         free(nargv);
 143         return -1;
 144 }
 145
 146
 147 int execl_perf_cmd(const char *cmd,...)
 148 {
 149         int argc;
 150         const char *argv[MAX_ARGS + 1];
 151         const char *arg;
 152         va_list param;
 153
 154         va_start(param, cmd);
 155         argv[0] = cmd;
 156         argc = 1;
 157         while (argc < MAX_ARGS) {
 158                 arg = argv[argc++] = va_arg(param, char *);
 159                 if (!arg)
 160                         break;
 161         }
 162         va_end(param);
 163         if (MAX_ARGS <= argc)
 164                 return error("too many args to run %s", cmd);
 165
 166         argv[argc] = NULL;
 167         return execv_perf_cmd(argv);
 168 }