tools/perf/perf.c

   1 /*
   2  * perf.c
   3  *
   4  * Performance analysis utility.
   5  *
   6  * This is the main hub from which the sub-commands (perf stat,
   7  * perf top, perf record, perf report, etc.) are started.
   8  */
   9 #include "builtin.h"
  10
  11 #include "util/exec_cmd.h"
  12 #include "util/cache.h"
  13 #include "util/quote.h"
  14 #include "util/run-command.h"
  15
  16 const char perf_usage_string[] =
  17         "perf [--version] [--help] COMMAND [ARGS]";
  18
  19 const char perf_more_info_string[] =
  20         "See 'perf help COMMAND' for more information on a specific command.";
  21
  22 static int use_pager = -1;
  23 struct pager_config {
  24         const char *cmd;
  25         int val;
  26 };
  27
  28 static int pager_command_config(const char *var, const char *value, void *data)
  29 {
  30         struct pager_config *c = data;
  31         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  32                 c->val = perf_config_bool(var, value);
  33         return 0;
  34 }
  35
  36 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  37 int check_pager_config(const char *cmd)
  38 {
  39         struct pager_config c;
  40         c.cmd = cmd;
  41         c.val = -1;
  42         perf_config(pager_command_config, &c);
  43         return c.val;
  44 }
  45
  46 static void commit_pager_choice(void) {
  47         switch (use_pager) {
  48         case 0:
  49                 setenv("PERF_PAGER", "cat", 1);
  50                 break;
  51         case 1:
  52                 /* setup_pager(); */
  53                 break;
  54         default:
  55                 break;
  56         }
  57 }
  58
  59 static int handle_options(const char*** argv, int* argc, int* envchanged)
  60 {
  61         int handled = 0;
  62
  63         while (*argc > 0) {
  64                 const char *cmd = (*argv)[0];
  65                 if (cmd[0] != '-')
  66                         break;
  67
  68                 /*
  69                  * For legacy reasons, the "version" and "help"
  70                  * commands can be written with "--" prepended
  71                  * to make them look like flags.
  72                  */
  73                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  74                         break;
  75
  76                 /*
  77                  * Check remaining flags.
  78                  */
  79                 if (!prefixcmp(cmd, "--exec-path")) {
  80                         cmd += 11;
  81                         if (*cmd == '=')
  82                                 perf_set_argv_exec_path(cmd + 1);
  83                         else {
  84                                 puts(perf_exec_path());
  85                                 exit(0);
  86                         }
  87                 } else if (!strcmp(cmd, "--html-path")) {
  88                         puts(system_path(PERF_HTML_PATH));
  89                         exit(0);
  90                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  91                         use_pager = 1;
  92                 } else if (!strcmp(cmd, "--no-pager")) {
  93                         use_pager = 0;
  94                         if (envchanged)
  95                                 *envchanged = 1;
  96                 } else if (!strcmp(cmd, "--perf-dir")) {
  97                         if (*argc < 2) {
  98                                 fprintf(stderr, "No directory given for --perf-dir.\n" );
  99                                 usage(perf_usage_string);
 100                         }
 101                         setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
 102                         if (envchanged)
 103                                 *envchanged = 1;
 104                         (*argv)++;
 105                         (*argc)--;
 106                         handled++;
 107                 } else if (!prefixcmp(cmd, "--perf-dir=")) {
 108                         setenv(PERF_DIR_ENVIRONMENT, cmd + 10, 1);
 109                         if (envchanged)
 110                                 *envchanged = 1;
 111                 } else if (!strcmp(cmd, "--work-tree")) {
 112                         if (*argc < 2) {
 113                                 fprintf(stderr, "No directory given for --work-tree.\n" );
 114                                 usage(perf_usage_string);
 115                         }
 116                         setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 117                         if (envchanged)
 118                                 *envchanged = 1;
 119                         (*argv)++;
 120                         (*argc)--;
 121                 } else if (!prefixcmp(cmd, "--work-tree=")) {
 122                         setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 123                         if (envchanged)
 124                                 *envchanged = 1;
 125                 } else {
 126                         fprintf(stderr, "Unknown option: %s\n", cmd);
 127                         usage(perf_usage_string);
 128                 }
 129
 130                 (*argv)++;
 131                 (*argc)--;
 132                 handled++;
 133         }
 134         return handled;
 135 }
 136
 137 static int handle_alias(int *argcp, const char ***argv)
 138 {
 139         int envchanged = 0, ret = 0, saved_errno = errno;
 140         int count, option_count;
 141         const char** new_argv;
 142         const char *alias_command;
 143         char *alias_string;
 144
 145         alias_command = (*argv)[0];
 146         alias_string = alias_lookup(alias_command);
 147         if (alias_string) {
 148                 if (alias_string[0] == '!') {
 149                         if (*argcp > 1) {
 150                                 struct strbuf buf;
 151
 152                                 strbuf_init(&buf, PATH_MAX);
 153                                 strbuf_addstr(&buf, alias_string);
 154                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 155                                 free(alias_string);
 156                                 alias_string = buf.buf;
 157                         }
 158                         ret = system(alias_string + 1);
 159                         if (ret >= 0 && WIFEXITED(ret) &&
 160                             WEXITSTATUS(ret) != 127)
 161                                 exit(WEXITSTATUS(ret));
 162                         die("Failed to run '%s' when expanding alias '%s'",
 163                             alias_string + 1, alias_command);
 164                 }
 165                 count = split_cmdline(alias_string, &new_argv);
 166                 if (count < 0)
 167                         die("Bad alias.%s string", alias_command);
 168                 option_count = handle_options(&new_argv, &count, &envchanged);
 169                 if (envchanged)
 170                         die("alias '%s' changes environment variables\n"
 171                                  "You can use '!perf' in the alias to do this.",
 172                                  alias_command);
 173                 memmove(new_argv - option_count, new_argv,
 174                                 count * sizeof(char *));
 175                 new_argv -= option_count;
 176
 177                 if (count < 1)
 178                         die("empty alias for %s", alias_command);
 179
 180                 if (!strcmp(alias_command, new_argv[0]))
 181                         die("recursive alias: %s", alias_command);
 182
 183                 new_argv = realloc(new_argv, sizeof(char*) *
 184                                     (count + *argcp + 1));
 185                 /* insert after command name */
 186                 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
 187                 new_argv[count+*argcp] = NULL;
 188
 189                 *argv = new_argv;
 190                 *argcp += count - 1;
 191
 192                 ret = 1;
 193         }
 194
 195         errno = saved_errno;
 196
 197         return ret;
 198 }
 199
 200 const char perf_version_string[] = PERF_VERSION;
 201
 202 #define RUN_SETUP       (1<<0)
 203 #define USE_PAGER       (1<<1)
 204 /*
 205  * require working tree to be present -- anything uses this needs
 206  * RUN_SETUP for reading from the configuration file.
 207  */
 208 #define NEED_WORK_TREE  (1<<2)
 209
 210 struct cmd_struct {
 211         const char *cmd;
 212         int (*fn)(int, const char **, const char *);
 213         int option;
 214 };
 215
 216 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 217 {
 218         int status;
 219         struct stat st;
 220         const char *prefix;
 221
 222         prefix = NULL;
 223         if (p->option & RUN_SETUP)
 224                 prefix = NULL; /* setup_perf_directory(); */
 225
 226         if (use_pager == -1 && p->option & RUN_SETUP)
 227                 use_pager = check_pager_config(p->cmd);
 228         if (use_pager == -1 && p->option & USE_PAGER)
 229                 use_pager = 1;
 230         commit_pager_choice();
 231
 232         status = p->fn(argc, argv, prefix);
 233         if (status)
 234                 return status & 0xff;
 235
 236         /* Somebody closed stdout? */
 237         if (fstat(fileno(stdout), &st))
 238                 return 0;
 239         /* Ignore write errors for pipes and sockets.. */
 240         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 241                 return 0;
 242
 243         /* Check for ENOSPC and EIO errors.. */
 244         if (fflush(stdout))
 245                 die("write failure on standard output: %s", strerror(errno));
 246         if (ferror(stdout))
 247                 die("unknown write failure on standard output");
 248         if (fclose(stdout))
 249                 die("close failed on standard output: %s", strerror(errno));
 250         return 0;
 251 }
 252
 253 static void handle_internal_command(int argc, const char **argv)
 254 {
 255         const char *cmd = argv[0];
 256         static struct cmd_struct commands[] = {
 257                 { "help", cmd_help, 0 },
 258                 { "list", cmd_list, 0 },
 259                 { "record", cmd_record, 0 },
 260                 { "report", cmd_report, 0 },
 261                 { "stat", cmd_stat, 0 },
 262                 { "top", cmd_top, 0 },
 263                 { "annotate", cmd_annotate, 0 },
 264                 { "version", cmd_version, 0 },
 265         };
 266         unsigned int i;
 267         static const char ext[] = STRIP_EXTENSION;
 268
 269         if (sizeof(ext) > 1) {
 270                 i = strlen(argv[0]) - strlen(ext);
 271                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 272                         char *argv0 = strdup(argv[0]);
 273                         argv[0] = cmd = argv0;
 274                         argv0[i] = '\0';
 275                 }
 276         }
 277
 278         /* Turn "perf cmd --help" into "perf help cmd" */
 279         if (argc > 1 && !strcmp(argv[1], "--help")) {
 280                 argv[1] = argv[0];
 281                 argv[0] = cmd = "help";
 282         }
 283
 284         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 285                 struct cmd_struct *p = commands+i;
 286                 if (strcmp(p->cmd, cmd))
 287                         continue;
 288                 exit(run_builtin(p, argc, argv));
 289         }
 290 }
 291
 292 static void execv_dashed_external(const char **argv)
 293 {
 294         struct strbuf cmd = STRBUF_INIT;
 295         const char *tmp;
 296         int status;
 297
 298         strbuf_addf(&cmd, "perf-%s", argv[0]);
 299
 300         /*
 301          * argv[0] must be the perf command, but the argv array
 302          * belongs to the caller, and may be reused in
 303          * subsequent loop iterations. Save argv[0] and
 304          * restore it on error.
 305          */
 306         tmp = argv[0];
 307         argv[0] = cmd.buf;
 308
 309         /*
 310          * if we fail because the command is not found, it is
 311          * OK to return. Otherwise, we just pass along the status code.
 312          */
 313         status = run_command_v_opt(argv, 0);
 314         if (status != -ERR_RUN_COMMAND_EXEC) {
 315                 if (IS_RUN_COMMAND_ERR(status))
 316                         die("unable to run '%s'", argv[0]);
 317                 exit(-status);
 318         }
 319         errno = ENOENT; /* as if we called execvp */
 320
 321         argv[0] = tmp;
 322
 323         strbuf_release(&cmd);
 324 }
 325
 326 static int run_argv(int *argcp, const char ***argv)
 327 {
 328         int done_alias = 0;
 329
 330         while (1) {
 331                 /* See if it's an internal command */
 332                 handle_internal_command(*argcp, *argv);
 333
 334                 /* .. then try the external ones */
 335                 execv_dashed_external(*argv);
 336
 337                 /* It could be an alias -- this works around the insanity
 338                  * of overriding "perf log" with "perf show" by having
 339                  * alias.log = show
 340                  */
 341                 if (done_alias || !handle_alias(argcp, argv))
 342                         break;
 343                 done_alias = 1;
 344         }
 345
 346         return done_alias;
 347 }
 348
 349
 350 int main(int argc, const char **argv)
 351 {
 352         const char *cmd;
 353
 354         cmd = perf_extract_argv0_path(argv[0]);
 355         if (!cmd)
 356                 cmd = "perf-help";
 357
 358         /*
 359          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 360          *
 361          *  - cannot take flags in between the "perf" and the "xxxx".
 362          *  - cannot execute it externally (since it would just do
 363          *    the same thing over again)
 364          *
 365          * So we just directly call the internal command handler, and
 366          * die if that one cannot handle it.
 367          */
 368         if (!prefixcmp(cmd, "perf-")) {
 369                 cmd += 5;
 370                 argv[0] = cmd;
 371                 handle_internal_command(argc, argv);
 372                 die("cannot handle %s internally", cmd);
 373         }
 374
 375         /* Look for flags.. */
 376         argv++;
 377         argc--;
 378         handle_options(&argv, &argc, NULL);
 379         commit_pager_choice();
 380         if (argc > 0) {
 381                 if (!prefixcmp(argv[0], "--"))
 382                         argv[0] += 2;
 383         } else {
 384                 /* The user didn't specify a command; give them help */
 385                 printf("\n usage: %s\n\n", perf_usage_string);
 386                 list_common_cmds_help();
 387                 printf("\n %s\n\n", perf_more_info_string);
 388                 exit(1);
 389         }
 390         cmd = argv[0];
 391
 392         /*
 393          * We use PATH to find perf commands, but we prepend some higher
 394          * precidence paths: the "--exec-path" option, the PERF_EXEC_PATH
 395          * environment, and the $(perfexecdir) from the Makefile at build
 396          * time.
 397          */
 398         setup_path();
 399
 400         while (1) {
 401                 static int done_help = 0;
 402                 static int was_alias = 0;
 403
 404                 was_alias = run_argv(&argc, &argv);
 405                 if (errno != ENOENT)
 406                         break;
 407
 408                 if (was_alias) {
 409                         fprintf(stderr, "Expansion of alias '%s' failed; "
 410                                 "'%s' is not a perf-command\n",
 411                                 cmd, argv[0]);
 412                         exit(1);
 413                 }
 414                 if (!done_help) {
 415                         cmd = argv[0] = help_unknown_cmd(cmd);
 416                         done_help = 1;
 417                 } else
 418                         break;
 419         }
 420
 421         fprintf(stderr, "Failed to run command '%s': %s\n",
 422                 cmd, strerror(errno));
 423
 424         return 1;
 425 }