1 files changed, 411 insertions, 0 deletions

diff --git a/Documentation/perf_counter/perf.c b/Documentation/perf_counter/perf.c
new file mode 100644
index 000000000000..9256f6a16446
--- /dev/null
+++ b/Documentation/perf_counter/perf.c
@@ -0,0 +1,411 @@
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "cache.h"
+//#include "quote.h"
+#include "run-command.h"
+
+const char perf_usage_string[] =
+        "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]";
+
+const char perf_more_info_string[] =
+        "See 'perf help COMMAND' for more information on a specific command.";
+
+static int use_pager = -1;
+struct pager_config {
+        const char *cmd;
+        int val;
+};
+
+static int pager_command_config(const char *var, const char *value, void *data)
+{
+        struct pager_config *c = data;
+        if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
+                c->val = perf_config_bool(var, value);
+        return 0;
+}
+
+/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
+int check_pager_config(const char *cmd)
+{
+        struct pager_config c;
+        c.cmd = cmd;
+        c.val = -1;
+        perf_config(pager_command_config, &c);
+        return c.val;
+}
+
+static void commit_pager_choice(void) {
+        switch (use_pager) {
+        case 0:
+                setenv("PERF_PAGER", "cat", 1);
+                break;
+        case 1:
+                /* setup_pager(); */
+                break;
+        default:
+                break;
+        }
+}
+
+static int handle_options(const char*** argv, int* argc, int* envchanged)
+{
+        int handled = 0;
+
+        while (*argc > 0) {
+                const char *cmd = (*argv)[0];
+                if (cmd[0] != '-')
+                        break;
+
+                /*
+                 * For legacy reasons, the "version" and "help"
+                 * commands can be written with "--" prepended
+                 * to make them look like flags.
+                 */
+                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
+                        break;
+
+                /*
+                 * Check remaining flags.
+                 */
+                if (!prefixcmp(cmd, "--exec-path")) {
+                        cmd += 11;
+                        if (*cmd == '=')
+                                perf_set_argv_exec_path(cmd + 1);
+                        else {
+                                puts(perf_exec_path());
+                                exit(0);
+                        }
+                } else if (!strcmp(cmd, "--html-path")) {
+                        puts(system_path(PERF_HTML_PATH));
+                        exit(0);
+                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
+                        use_pager = 1;
+                } else if (!strcmp(cmd, "--no-pager")) {
+                        use_pager = 0;
+                        if (envchanged)
+                                *envchanged = 1;
+                } else if (!strcmp(cmd, "--perf-dir")) {
+                        if (*argc < 2) {
+                                fprintf(stderr, "No directory given for --perf-dir.\n" );
+                                usage(perf_usage_string);
+                        }
+                        setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
+                        if (envchanged)
+                                *envchanged = 1;
+                        (*argv)++;
+                        (*argc)--;
+                        handled++;
+                } else if (!prefixcmp(cmd, "--perf-dir=")) {
+                        setenv(PERF_DIR_ENVIRONMENT, cmd + 10, 1);
+                        if (envchanged)
+                                *envchanged = 1;
+                } else if (!strcmp(cmd, "--work-tree")) {
+                        if (*argc < 2) {
+                                fprintf(stderr, "No directory given for --work-tree.\n" );
+                                usage(perf_usage_string);
+                        }
+                        setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
+                        if (envchanged)
+                                *envchanged = 1;
+                        (*argv)++;
+                        (*argc)--;
+                } else if (!prefixcmp(cmd, "--work-tree=")) {
+                        setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
+                        if (envchanged)
+                                *envchanged = 1;
+                } else {
+                        fprintf(stderr, "Unknown option: %s\n", cmd);
+                        usage(perf_usage_string);
+                }
+
+                (*argv)++;
+                (*argc)--;
+                handled++;
+        }
+        return handled;
+}
+
+static int handle_alias(int *argcp, const char ***argv)
+{
+        int envchanged = 0, ret = 0, saved_errno = errno;
+        int count, option_count;
+        const char** new_argv;
+        const char *alias_command;
+        char *alias_string;
+        int unused_nonperf;
+
+        alias_command = (*argv)[0];
+        alias_string = alias_lookup(alias_command);
+        if (alias_string) {
+                if (alias_string[0] == '!') {
+                        if (*argcp > 1) {
+                                struct strbuf buf;
+
+                                strbuf_init(&buf, PATH_MAX);
+                                strbuf_addstr(&buf, alias_string);
+                                sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
+                                free(alias_string);
+                                alias_string = buf.buf;
+                        }
+                        ret = system(alias_string + 1);
+                        if (ret >= 0 && WIFEXITED(ret) &&
+                            WEXITSTATUS(ret) != 127)
+                                exit(WEXITSTATUS(ret));
+                        die("Failed to run '%s' when expanding alias '%s'",
+                            alias_string + 1, alias_command);
+                }
+                count = split_cmdline(alias_string, &new_argv);
+                if (count < 0)
+                        die("Bad alias.%s string", alias_command);
+                option_count = handle_options(&new_argv, &count, &envchanged);
+                if (envchanged)
+                        die("alias '%s' changes environment variables\n"
+                                 "You can use '!perf' in the alias to do this.",
+                                 alias_command);
+                memmove(new_argv - option_count, new_argv,
+                                count * sizeof(char *));
+                new_argv -= option_count;
+
+                if (count < 1)
+                        die("empty alias for %s", alias_command);
+
+                if (!strcmp(alias_command, new_argv[0]))
+                        die("recursive alias: %s", alias_command);
+
+                new_argv = realloc(new_argv, sizeof(char*) *
+                                    (count + *argcp + 1));
+                /* insert after command name */
+                memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
+                new_argv[count+*argcp] = NULL;
+
+                *argv = new_argv;
+                *argcp += count - 1;
+
+                ret = 1;
+        }
+
+        errno = saved_errno;
+
+        return ret;
+}
+
+const char perf_version_string[] = PERF_VERSION;
+
+#define RUN_SETUP       (1<<0)
+#define USE_PAGER       (1<<1)
+/*
+ * require working tree to be present -- anything uses this needs
+ * RUN_SETUP for reading from the configuration file.
+ */
+#define NEED_WORK_TREE  (1<<2)
+
+struct cmd_struct {
+        const char *cmd;
+        int (*fn)(int, const char **, const char *);
+        int option;
+};
+
+static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
+{
+        int status;
+        struct stat st;
+        const char *prefix;
+
+        prefix = NULL;
+        if (p->option & RUN_SETUP)
+                prefix = NULL; /* setup_perf_directory(); */
+
+        if (use_pager == -1 && p->option & RUN_SETUP)
+                use_pager = check_pager_config(p->cmd);
+        if (use_pager == -1 && p->option & USE_PAGER)
+                use_pager = 1;
+        commit_pager_choice();
+
+        if (p->option & NEED_WORK_TREE)
+                /* setup_work_tree() */;
+
+        status = p->fn(argc, argv, prefix);
+        if (status)
+                return status & 0xff;
+
+        /* Somebody closed stdout? */
+        if (fstat(fileno(stdout), &st))
+                return 0;
+        /* Ignore write errors for pipes and sockets.. */
+        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
+                return 0;
+
+        /* Check for ENOSPC and EIO errors.. */
+        if (fflush(stdout))
+                die("write failure on standard output: %s", strerror(errno));
+        if (ferror(stdout))
+                die("unknown write failure on standard output");
+        if (fclose(stdout))
+                die("close failed on standard output: %s", strerror(errno));
+        return 0;
+}
+
+static void handle_internal_command(int argc, const char **argv)
+{
+        const char *cmd = argv[0];
+        static struct cmd_struct commands[] = {
+                { "top", cmd_top, 0 },
+        };
+        int i;
+        static const char ext[] = STRIP_EXTENSION;
+
+        if (sizeof(ext) > 1) {
+                i = strlen(argv[0]) - strlen(ext);
+                if (i > 0 && !strcmp(argv[0] + i, ext)) {
+                        char *argv0 = strdup(argv[0]);
+                        argv[0] = cmd = argv0;
+                        argv0[i] = '\0';
+                }
+        }
+
+        /* Turn "perf cmd --help" into "perf help cmd" */
+        if (argc > 1 && !strcmp(argv[1], "--help")) {
+                argv[1] = argv[0];
+                argv[0] = cmd = "help";
+        }
+
+        for (i = 0; i < ARRAY_SIZE(commands); i++) {
+                struct cmd_struct *p = commands+i;
+                if (strcmp(p->cmd, cmd))
+                        continue;
+                exit(run_builtin(p, argc, argv));
+        }
+}
+
+static void execv_dashed_external(const char **argv)
+{
+        struct strbuf cmd = STRBUF_INIT;
+        const char *tmp;
+        int status;
+
+        strbuf_addf(&cmd, "perf-%s", argv[0]);
+
+        /*
+         * argv[0] must be the perf command, but the argv array
+         * belongs to the caller, and may be reused in
+         * subsequent loop iterations. Save argv[0] and
+         * restore it on error.
+         */
+        tmp = argv[0];
+        argv[0] = cmd.buf;
+
+        /*
+         * if we fail because the command is not found, it is
+         * OK to return. Otherwise, we just pass along the status code.
+         */
+        status = run_command_v_opt(argv, 0);
+        if (status != -ERR_RUN_COMMAND_EXEC) {
+                if (IS_RUN_COMMAND_ERR(status))
+                        die("unable to run '%s'", argv[0]);
+                exit(-status);
+        }
+        errno = ENOENT; /* as if we called execvp */
+
+        argv[0] = tmp;
+
+        strbuf_release(&cmd);
+}
+
+static int run_argv(int *argcp, const char ***argv)
+{
+        int done_alias = 0;
+
+        while (1) {
+                /* See if it's an internal command */
+                handle_internal_command(*argcp, *argv);
+
+                /* .. then try the external ones */
+                execv_dashed_external(*argv);
+
+                /* It could be an alias -- this works around the insanity
+                 * of overriding "perf log" with "perf show" by having
+                 * alias.log = show
+                 */
+                if (done_alias || !handle_alias(argcp, argv))
+                        break;
+                done_alias = 1;
+        }
+
+        return done_alias;
+}
+
+
+int main(int argc, const char **argv)
+{
+        const char *cmd;
+
+        cmd = perf_extract_argv0_path(argv[0]);
+        if (!cmd)
+                cmd = "perf-help";
+
+        /*
+         * "perf-xxxx" is the same as "perf xxxx", but we obviously:
+         *
+         *  - cannot take flags in between the "perf" and the "xxxx".
+         *  - cannot execute it externally (since it would just do
+         *    the same thing over again)
+         *
+         * So we just directly call the internal command handler, and
+         * die if that one cannot handle it.
+         */
+        if (!prefixcmp(cmd, "perf-")) {
+                cmd += 4;
+                argv[0] = cmd;
+                handle_internal_command(argc, argv);
+                die("cannot handle %s internally", cmd);
+        }
+
+        /* Look for flags.. */
+        argv++;
+        argc--;
+        handle_options(&argv, &argc, NULL);
+        commit_pager_choice();
+        if (argc > 0) {
+                if (!prefixcmp(argv[0], "--"))
+                        argv[0] += 2;
+        } else {
+                /* The user didn't specify a command; give them help */
+                printf("usage: %s\n\n", perf_usage_string);
+                list_common_cmds_help();
+                printf("\n%s\n", perf_more_info_string);
+                exit(1);
+        }
+        cmd = argv[0];
+
+        /*
+         * We use PATH to find perf commands, but we prepend some higher
+         * precidence paths: the "--exec-path" option, the PERF_EXEC_PATH
+         * environment, and the $(perfexecdir) from the Makefile at build
+         * time.
+         */
+        setup_path();
+
+        while (1) {
+                static int done_help = 0;
+                static int was_alias = 0;
+                was_alias = run_argv(&argc, &argv);
+                if (errno != ENOENT)
+                        break;
+                if (was_alias) {
+                        fprintf(stderr, "Expansion of alias '%s' failed; "
+                                "'%s' is not a perf-command\n",
+                                cmd, argv[0]);
+                        exit(1);
+                }
+                if (!done_help) {
+                        cmd = argv[0] = help_unknown_cmd(cmd);
+                        done_help = 1;
+                } else
+                        break;
+        }
+
+        fprintf(stderr, "Failed to run command '%s': %s\n",
+                cmd, strerror(errno));
+
+        return 1;
+}