perf buildid-list: New plumbing command

With this we can list the buildids in a perf.data file so that
we can pipe them to other, distro specific tools that from the
buildids can figure out separate packages (foo-debuginfo) where
we can find the matching symtabs so that perf report can do its
job.

E.g:

[acme@doppio linux-2.6-tip]$ perf buildid-list | head -5
8e08b117e5458ad3f85da16d42d0fc5cd21c5869
520c2387a587cc5acfcf881e27dba1caaeab4b1f
ec8dd400904ddfcac8b1c343263a790f977159dc
7caedbca5a6d8ab39a7fe44bd28c07d3e14a3f3f
379bb828fd08859dbea73279f04abefabc95a6a3
[acme@doppio linux-2.6-tip]$ perf buildid-list -v | head -5
8e08b117e5458ad3f85da16d42d0fc5cd21c5869 /sbin/init
520c2387a587cc5acfcf881e27dba1caaeab4b1f /lib64/ld-2.10.1.so
ec8dd400904ddfcac8b1c343263a790f977159dc /lib64/libc-2.10.1.so
7caedbca5a6d8ab39a7fe44bd28c07d3e14a3f3f /sbin/udevd
379bb828fd08859dbea73279f04abefabc95a6a3 /lib64/libdl-2.10.1.so
[acme@doppio linux-2.6-tip]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258396365-29217-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c
new file mode 100644
index 0000000..2e377e1
--- /dev/null
+++ b/tools/perf/builtin-buildid-list.c
@@ -0,0 +1,116 @@
+/*
+ * builtin-buildid-list.c
+ *
+ * Builtin buildid-list command: list buildids in perf.data
+ *
+ * Copyright (C) 2009, Red Hat Inc.
+ * Copyright (C) 2009, Arnaldo Carvalho de Melo <acme@redhat.com>
+ */
+#include "builtin.h"
+#include "perf.h"
+#include "util/cache.h"
+#include "util/data_map.h"
+#include "util/debug.h"
+#include "util/header.h"
+#include "util/parse-options.h"
+#include "util/symbol.h"
+
+static char const *input_name = "perf.data";
+static int force;
+
+static const char *const buildid_list_usage[] = {
+	"perf report [<options>]",
+	NULL
+};
+
+static const struct option options[] = {
+	OPT_STRING('i', "input", &input_name, "file",
+		    "input file name"),
+	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
+	OPT_BOOLEAN('v', "verbose", &verbose,
+		    "be more verbose (show counter open errors, etc)"),
+	OPT_END()
+};
+
+static int perf_file_section__process_buildids(struct perf_file_section *self,
+					       int feat, int fd)
+{
+	if (feat != HEADER_BUILD_ID)
+		return 0;
+
+	if (lseek(fd, self->offset, SEEK_SET) < 0) {
+		pr_warning("Failed to lseek to %Ld offset for buildids!\n",
+			   self->offset);
+		return -1;
+	}
+
+	if (perf_header__read_build_ids(fd, self->offset, self->size)) {
+		pr_warning("Failed to read buildids!\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int __cmd_buildid_list(void)
+{
+	int err = -1;
+	struct perf_header *header;
+	struct perf_file_header f_header;
+	struct stat input_stat;
+	int input = open(input_name, O_RDONLY);
+
+	if (input < 0) {
+		pr_err("failed to open file: %s", input_name);
+		if (!strcmp(input_name, "perf.data"))
+			pr_err("  (try 'perf record' first)");
+		pr_err("\n");
+		goto out;
+	}
+
+	err = fstat(input, &input_stat);
+	if (err < 0) {
+		perror("failed to stat file");
+		goto out_close;
+	}
+
+	if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
+		pr_err("file %s not owned by current user or root\n",
+		       input_name);
+		goto out_close;
+	}
+
+	if (!input_stat.st_size) {
+		pr_info("zero-sized file, nothing to do!\n");
+		goto out_close;
+	}
+
+	err = -1;
+	header = perf_header__new();
+	if (header == NULL)
+		goto out_close;
+
+	if (perf_file_header__read(&f_header, header, input) < 0) {
+		pr_warning("incompatible file format");
+		goto out_close;
+	}
+
+	err = perf_header__process_sections(header, input,
+				         perf_file_section__process_buildids);
+
+	if (err < 0)
+		goto out_close;
+
+	dsos__fprintf_buildid(stdout);
+out_close:
+	close(input);
+out:
+	return err;
+}
+
+int cmd_buildid_list(int argc, const char **argv, const char *prefix __used)
+{
+	argc = parse_options(argc, argv, options, buildid_list_usage, 0);
+	setup_pager();
+	return __cmd_buildid_list();
+}