perf_counter tools: clean up after introduction of the Git command framework
[linux-2.6] / Documentation / perf_counter / perf.c
1 #include "builtin.h"
2 #include "exec_cmd.h"
3 #include "cache.h"
4 #include "quote.h"
5 #include "run-command.h"
6
7 const char perf_usage_string[] =
8         "perf [--version] [--exec-path[=PERF_EXEC_PATH]] [--html-path] [-p|--paginate|--no-pager] [--bare] [--perf-dir=PERF_DIR] [--work-tree=PERF_WORK_TREE] [--help] COMMAND [ARGS]";
9
10 const char perf_more_info_string[] =
11         "See 'perf help COMMAND' for more information on a specific command.";
12
13 static int use_pager = -1;
14 struct pager_config {
15         const char *cmd;
16         int val;
17 };
18
19 static int pager_command_config(const char *var, const char *value, void *data)
20 {
21         struct pager_config *c = data;
22         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
23                 c->val = perf_config_bool(var, value);
24         return 0;
25 }
26
27 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
28 int check_pager_config(const char *cmd)
29 {
30         struct pager_config c;
31         c.cmd = cmd;
32         c.val = -1;
33         perf_config(pager_command_config, &c);
34         return c.val;
35 }
36
37 static void commit_pager_choice(void) {
38         switch (use_pager) {
39         case 0:
40                 setenv("PERF_PAGER", "cat", 1);
41                 break;
42         case 1:
43                 /* setup_pager(); */
44                 break;
45         default:
46                 break;
47         }
48 }
49
50 static int handle_options(const char*** argv, int* argc, int* envchanged)
51 {
52         int handled = 0;
53
54         while (*argc > 0) {
55                 const char *cmd = (*argv)[0];
56                 if (cmd[0] != '-')
57                         break;
58
59                 /*
60                  * For legacy reasons, the "version" and "help"
61                  * commands can be written with "--" prepended
62                  * to make them look like flags.
63                  */
64                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
65                         break;
66
67                 /*
68                  * Check remaining flags.
69                  */
70                 if (!prefixcmp(cmd, "--exec-path")) {
71                         cmd += 11;
72                         if (*cmd == '=')
73                                 perf_set_argv_exec_path(cmd + 1);
74                         else {
75                                 puts(perf_exec_path());
76                                 exit(0);
77                         }
78                 } else if (!strcmp(cmd, "--html-path")) {
79                         puts(system_path(PERF_HTML_PATH));
80                         exit(0);
81                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
82                         use_pager = 1;
83                 } else if (!strcmp(cmd, "--no-pager")) {
84                         use_pager = 0;
85                         if (envchanged)
86                                 *envchanged = 1;
87                 } else if (!strcmp(cmd, "--perf-dir")) {
88                         if (*argc < 2) {
89                                 fprintf(stderr, "No directory given for --perf-dir.\n" );
90                                 usage(perf_usage_string);
91                         }
92                         setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
93                         if (envchanged)
94                                 *envchanged = 1;
95                         (*argv)++;
96                         (*argc)--;
97                         handled++;
98                 } else if (!prefixcmp(cmd, "--perf-dir=")) {
99                         setenv(PERF_DIR_ENVIRONMENT, cmd + 10, 1);
100                         if (envchanged)
101                                 *envchanged = 1;
102                 } else if (!strcmp(cmd, "--work-tree")) {
103                         if (*argc < 2) {
104                                 fprintf(stderr, "No directory given for --work-tree.\n" );
105                                 usage(perf_usage_string);
106                         }
107                         setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
108                         if (envchanged)
109                                 *envchanged = 1;
110                         (*argv)++;
111                         (*argc)--;
112                 } else if (!prefixcmp(cmd, "--work-tree=")) {
113                         setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
114                         if (envchanged)
115                                 *envchanged = 1;
116                 } else {
117                         fprintf(stderr, "Unknown option: %s\n", cmd);
118                         usage(perf_usage_string);
119                 }
120
121                 (*argv)++;
122                 (*argc)--;
123                 handled++;
124         }
125         return handled;
126 }
127
128 static int handle_alias(int *argcp, const char ***argv)
129 {
130         int envchanged = 0, ret = 0, saved_errno = errno;
131         int count, option_count;
132         const char** new_argv;
133         const char *alias_command;
134         char *alias_string;
135
136         alias_command = (*argv)[0];
137         alias_string = alias_lookup(alias_command);
138         if (alias_string) {
139                 if (alias_string[0] == '!') {
140                         if (*argcp > 1) {
141                                 struct strbuf buf;
142
143                                 strbuf_init(&buf, PATH_MAX);
144                                 strbuf_addstr(&buf, alias_string);
145                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
146                                 free(alias_string);
147                                 alias_string = buf.buf;
148                         }
149                         ret = system(alias_string + 1);
150                         if (ret >= 0 && WIFEXITED(ret) &&
151                             WEXITSTATUS(ret) != 127)
152                                 exit(WEXITSTATUS(ret));
153                         die("Failed to run '%s' when expanding alias '%s'",
154                             alias_string + 1, alias_command);
155                 }
156                 count = split_cmdline(alias_string, &new_argv);
157                 if (count < 0)
158                         die("Bad alias.%s string", alias_command);
159                 option_count = handle_options(&new_argv, &count, &envchanged);
160                 if (envchanged)
161                         die("alias '%s' changes environment variables\n"
162                                  "You can use '!perf' in the alias to do this.",
163                                  alias_command);
164                 memmove(new_argv - option_count, new_argv,
165                                 count * sizeof(char *));
166                 new_argv -= option_count;
167
168                 if (count < 1)
169                         die("empty alias for %s", alias_command);
170
171                 if (!strcmp(alias_command, new_argv[0]))
172                         die("recursive alias: %s", alias_command);
173
174                 new_argv = realloc(new_argv, sizeof(char*) *
175                                     (count + *argcp + 1));
176                 /* insert after command name */
177                 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
178                 new_argv[count+*argcp] = NULL;
179
180                 *argv = new_argv;
181                 *argcp += count - 1;
182
183                 ret = 1;
184         }
185
186         errno = saved_errno;
187
188         return ret;
189 }
190
191 const char perf_version_string[] = PERF_VERSION;
192
193 #define RUN_SETUP       (1<<0)
194 #define USE_PAGER       (1<<1)
195 /*
196  * require working tree to be present -- anything uses this needs
197  * RUN_SETUP for reading from the configuration file.
198  */
199 #define NEED_WORK_TREE  (1<<2)
200
201 struct cmd_struct {
202         const char *cmd;
203         int (*fn)(int, const char **, const char *);
204         int option;
205 };
206
207 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
208 {
209         int status;
210         struct stat st;
211         const char *prefix;
212
213         prefix = NULL;
214         if (p->option & RUN_SETUP)
215                 prefix = NULL; /* setup_perf_directory(); */
216
217         if (use_pager == -1 && p->option & RUN_SETUP)
218                 use_pager = check_pager_config(p->cmd);
219         if (use_pager == -1 && p->option & USE_PAGER)
220                 use_pager = 1;
221         commit_pager_choice();
222
223         if (p->option & NEED_WORK_TREE)
224                 /* setup_work_tree() */;
225
226         status = p->fn(argc, argv, prefix);
227         if (status)
228                 return status & 0xff;
229
230         /* Somebody closed stdout? */
231         if (fstat(fileno(stdout), &st))
232                 return 0;
233         /* Ignore write errors for pipes and sockets.. */
234         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
235                 return 0;
236
237         /* Check for ENOSPC and EIO errors.. */
238         if (fflush(stdout))
239                 die("write failure on standard output: %s", strerror(errno));
240         if (ferror(stdout))
241                 die("unknown write failure on standard output");
242         if (fclose(stdout))
243                 die("close failed on standard output: %s", strerror(errno));
244         return 0;
245 }
246
247 static void handle_internal_command(int argc, const char **argv)
248 {
249         const char *cmd = argv[0];
250         static struct cmd_struct commands[] = {
251                 { "top", cmd_top, 0 },
252         };
253         int i;
254         static const char ext[] = STRIP_EXTENSION;
255
256         if (sizeof(ext) > 1) {
257                 i = strlen(argv[0]) - strlen(ext);
258                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
259                         char *argv0 = strdup(argv[0]);
260                         argv[0] = cmd = argv0;
261                         argv0[i] = '\0';
262                 }
263         }
264
265         /* Turn "perf cmd --help" into "perf help cmd" */
266         if (argc > 1 && !strcmp(argv[1], "--help")) {
267                 argv[1] = argv[0];
268                 argv[0] = cmd = "help";
269         }
270
271         for (i = 0; i < ARRAY_SIZE(commands); i++) {
272                 struct cmd_struct *p = commands+i;
273                 if (strcmp(p->cmd, cmd))
274                         continue;
275                 exit(run_builtin(p, argc, argv));
276         }
277 }
278
279 static void execv_dashed_external(const char **argv)
280 {
281         struct strbuf cmd = STRBUF_INIT;
282         const char *tmp;
283         int status;
284
285         strbuf_addf(&cmd, "perf-%s", argv[0]);
286
287         /*
288          * argv[0] must be the perf command, but the argv array
289          * belongs to the caller, and may be reused in
290          * subsequent loop iterations. Save argv[0] and
291          * restore it on error.
292          */
293         tmp = argv[0];
294         argv[0] = cmd.buf;
295
296         /*
297          * if we fail because the command is not found, it is
298          * OK to return. Otherwise, we just pass along the status code.
299          */
300         status = run_command_v_opt(argv, 0);
301         if (status != -ERR_RUN_COMMAND_EXEC) {
302                 if (IS_RUN_COMMAND_ERR(status))
303                         die("unable to run '%s'", argv[0]);
304                 exit(-status);
305         }
306         errno = ENOENT; /* as if we called execvp */
307
308         argv[0] = tmp;
309
310         strbuf_release(&cmd);
311 }
312
313 static int run_argv(int *argcp, const char ***argv)
314 {
315         int done_alias = 0;
316
317         while (1) {
318                 /* See if it's an internal command */
319                 handle_internal_command(*argcp, *argv);
320
321                 /* .. then try the external ones */
322                 execv_dashed_external(*argv);
323
324                 /* It could be an alias -- this works around the insanity
325                  * of overriding "perf log" with "perf show" by having
326                  * alias.log = show
327                  */
328                 if (done_alias || !handle_alias(argcp, argv))
329                         break;
330                 done_alias = 1;
331         }
332
333         return done_alias;
334 }
335
336
337 int main(int argc, const char **argv)
338 {
339         const char *cmd;
340
341         cmd = perf_extract_argv0_path(argv[0]);
342         if (!cmd)
343                 cmd = "perf-help";
344
345         /*
346          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
347          *
348          *  - cannot take flags in between the "perf" and the "xxxx".
349          *  - cannot execute it externally (since it would just do
350          *    the same thing over again)
351          *
352          * So we just directly call the internal command handler, and
353          * die if that one cannot handle it.
354          */
355         if (!prefixcmp(cmd, "perf-")) {
356                 cmd += 4;
357                 argv[0] = cmd;
358                 handle_internal_command(argc, argv);
359                 die("cannot handle %s internally", cmd);
360         }
361
362         /* Look for flags.. */
363         argv++;
364         argc--;
365         handle_options(&argv, &argc, NULL);
366         commit_pager_choice();
367         if (argc > 0) {
368                 if (!prefixcmp(argv[0], "--"))
369                         argv[0] += 2;
370         } else {
371                 /* The user didn't specify a command; give them help */
372                 printf("usage: %s\n\n", perf_usage_string);
373                 list_common_cmds_help();
374                 printf("\n%s\n", perf_more_info_string);
375                 exit(1);
376         }
377         cmd = argv[0];
378
379         /*
380          * We use PATH to find perf commands, but we prepend some higher
381          * precidence paths: the "--exec-path" option, the PERF_EXEC_PATH
382          * environment, and the $(perfexecdir) from the Makefile at build
383          * time.
384          */
385         setup_path();
386
387         while (1) {
388                 static int done_help = 0;
389                 static int was_alias = 0;
390                 was_alias = run_argv(&argc, &argv);
391                 if (errno != ENOENT)
392                         break;
393                 if (was_alias) {
394                         fprintf(stderr, "Expansion of alias '%s' failed; "
395                                 "'%s' is not a perf-command\n",
396                                 cmd, argv[0]);
397                         exit(1);
398                 }
399                 if (!done_help) {
400                         cmd = argv[0] = help_unknown_cmd(cmd);
401                         done_help = 1;
402                 } else
403                         break;
404         }
405
406         fprintf(stderr, "Failed to run command '%s': %s\n",
407                 cmd, strerror(errno));
408
409         return 1;
410 }