perf tools: Get rid of write_or_die() from trace-event-info.c

Check return value of write and fail if error.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1363850332-25297-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 127 insertions, 55 deletions

diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index 91db6e8e4493..090e80d743db 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -106,17 +106,6 @@ static void put_tracing_file(char *file)
         free(file);
 }
 
-static ssize_t write_or_die(const void *buf, size_t len)
-{
-        int ret;
-
-        ret = write(output_fd, buf, len);
-        if (ret < 0)
-                die("writing to '%s'", output_file);
-
-        return ret;
-}
-
 int bigendian(void)
 {
         unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
@@ -127,29 +116,32 @@ int bigendian(void)
 }
 
 /* unfortunately, you can not stat debugfs or proc files for size */
-static void record_file(const char *file, size_t hdr_sz)
+static int record_file(const char *file, ssize_t hdr_sz)
 {
         unsigned long long size = 0;
         char buf[BUFSIZ], *sizep;
         off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
         int r, fd;
+        int err = -EIO;
 
         fd = open(file, O_RDONLY);
         if (fd < 0)
                 die("Can't read '%s'", file);
 
         /* put in zeros for file size, then fill true size later */
-        if (hdr_sz)
-                write_or_die(&size, hdr_sz);
+        if (hdr_sz) {
+                if (write(output_fd, &size, hdr_sz) != hdr_sz)
+                        goto out;
+        }
 
         do {
                 r = read(fd, buf, BUFSIZ);
                 if (r > 0) {
                         size += r;
-                        write_or_die(buf, r);
+                        if (write(output_fd, buf, r) != r)
+                                goto out;
                 }
         } while (r > 0);
-        close(fd);
 
         /* ugh, handle big-endian hdr_size == 4 */
         sizep = (char*)&size;
@@ -158,12 +150,18 @@ static void record_file(const char *file, size_t hdr_sz)
 
         if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0)
                 die("writing to %s", output_file);
+
+        err = 0;
+out:
+        close(fd);
+        return err;
 }
 
-static void read_header_files(void)
+static int read_header_files(void)
 {
         char *path;
         struct stat st;
+        int err = -EIO;
 
         path = get_tracing_file("events/header_page");
         if (!path)
@@ -172,8 +170,16 @@ static void read_header_files(void)
         if (stat(path, &st) < 0)
                 die("can't read '%s'", path);
 
-        write_or_die("header_page", 12);
-        record_file(path, 8);
+        if (write(output_fd, "header_page", 12) != 12) {
+                pr_debug("can't write header_page\n");
+                goto out;
+        }
+
+        if (record_file(path, 8) < 0) {
+                pr_debug("can't record header_page file\n");
+                goto out;
+        }
+
         put_tracing_file(path);
 
         path = get_tracing_file("events/header_event");
@@ -183,9 +189,20 @@ static void read_header_files(void)
         if (stat(path, &st) < 0)
                 die("can't read '%s'", path);
 
-        write_or_die("header_event", 13);
-        record_file(path, 8);
+        if (write(output_fd, "header_event", 13) != 13) {
+                pr_debug("can't write header_event\n");
+                goto out;
+        }
+
+        if (record_file(path, 8) < 0) {
+                pr_debug("can't record header_event file\n");
+                goto out;
+        }
+
+        err = 0;
+out:
         put_tracing_file(path);
+        return err;
 }
 
 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
@@ -232,7 +249,11 @@ static int copy_event_system(const char *sys, struct tracepoint_path *tps)
                 count++;
         }
 
-        write_or_die(&count, 4);
+        if (write(output_fd, &count, 4) != 4) {
+                err = -EIO;
+                pr_debug("can't write count\n");
+                goto out;
+        }
 
         rewinddir(dir);
         while ((dent = readdir(dir))) {
@@ -249,8 +270,13 @@ static int copy_event_system(const char *sys, struct tracepoint_path *tps)
                 sprintf(format, "%s/%s/format", sys, dent->d_name);
                 ret = stat(format, &st);
 
-                if (ret >= 0)
-                        record_file(format, 8);
+                if (ret >= 0) {
+                        err = record_file(format, 8);
+                        if (err) {
+                                free(format);
+                                goto out;
+                        }
+                }
                 free(format);
         }
         err = 0;
@@ -259,17 +285,20 @@ out:
         return err;
 }
 
-static void read_ftrace_files(struct tracepoint_path *tps)
+static int read_ftrace_files(struct tracepoint_path *tps)
 {
         char *path;
+        int ret;
 
         path = get_tracing_file("events/ftrace");
         if (!path)
                 die("can't get tracing/events/ftrace");
 
-        copy_event_system(path, tps);
+        ret = copy_event_system(path, tps);
 
         put_tracing_file(path);
+
+        return ret;
 }
 
 static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
@@ -312,7 +341,11 @@ static int read_event_files(struct tracepoint_path *tps)
                 count++;
         }
 
-        write_or_die(&count, 4);
+        if (write(output_fd, &count, 4) != 4) {
+                err = -EIO;
+                pr_debug("can't write count\n");
+                goto out;
+        }
 
         rewinddir(dir);
         while ((dent = readdir(dir))) {
@@ -330,8 +363,14 @@ static int read_event_files(struct tracepoint_path *tps)
                 sprintf(sys, "%s/%s", path, dent->d_name);
                 ret = stat(sys, &st);
                 if (ret >= 0) {
-                        write_or_die(dent->d_name, strlen(dent->d_name) + 1);
-                        copy_event_system(sys, tps);
+                        ssize_t size = strlen(dent->d_name) + 1;
+
+                        if (write(output_fd, dent->d_name, size) != size ||
+                            copy_event_system(sys, tps) < 0) {
+                                err = -EIO;
+                                free(sys);
+                                goto out;
+                        }
                 }
                 free(sys);
         }
@@ -343,29 +382,30 @@ out:
         return err;
 }
 
-static void read_proc_kallsyms(void)
+static int read_proc_kallsyms(void)
 {
         unsigned int size;
         const char *path = "/proc/kallsyms";
         struct stat st;
-        int ret;
+        int ret, err = 0;
 
         ret = stat(path, &st);
         if (ret < 0) {
                 /* not found */
                 size = 0;
-                write_or_die(&size, 4);
-                return;
+                if (write(output_fd, &size, 4) != 4)
+                        err = -EIO;
+                return err;
         }
-        record_file(path, 4);
+        return record_file(path, 4);
 }
 
-static void read_ftrace_printk(void)
+static int read_ftrace_printk(void)
 {
         unsigned int size;
         char *path;
         struct stat st;
-        int ret;
+        int ret, err = 0;
 
         path = get_tracing_file("printk_formats");
         if (!path)
@@ -375,13 +415,15 @@ static void read_ftrace_printk(void)
         if (ret < 0) {
                 /* not found */
                 size = 0;
-                write_or_die(&size, 4);
+                if (write(output_fd, &size, 4) != 4)
+                        err = -EIO;
                 goto out;
         }
-        record_file(path, 4);
+        err = record_file(path, 4);
 
 out:
         put_tracing_file(path);
+        return err;
 }
 
 static struct tracepoint_path *
@@ -428,9 +470,10 @@ bool have_tracepoints(struct list_head *pattrs)
         return false;
 }
 
-static void tracing_data_header(void)
+static int tracing_data_header(void)
 {
         char buf[20];
+        ssize_t size;
 
         /* just guessing this is someone's birthday.. ;) */
         buf[0] = 23;
@@ -438,9 +481,12 @@ static void tracing_data_header(void)
         buf[2] = 68;
         memcpy(buf + 3, "tracing", 7);
 
-        write_or_die(buf, 10);
+        if (write(output_fd, buf, 10) != 10)
+                return -1;
 
-        write_or_die(VERSION, strlen(VERSION) + 1);
+        size = strlen(VERSION) + 1;
+        if (write(output_fd, VERSION, size) != size)
+                return -1;
 
         /* save endian */
         if (bigendian())
@@ -450,14 +496,19 @@ static void tracing_data_header(void)
 
         read_trace_init(buf[0], buf[0]);
 
-        write_or_die(buf, 1);
+        if (write(output_fd, buf, 1) != 1)
+                return -1;
 
         /* save size of long */
         buf[0] = sizeof(long);
-        write_or_die(buf, 1);
+        if (write(output_fd, buf, 1) != 1)
+                return -1;
 
         /* save page_size */
-        write_or_die(&page_size, 4);
+        if (write(output_fd, &page_size, 4) != 4)
+                return -1;
+
+        return 0;
 }
 
 struct tracing_data *tracing_data_get(struct list_head *pattrs,
@@ -465,6 +516,7 @@ struct tracing_data *tracing_data_get(struct list_head *pattrs,
 {
         struct tracepoint_path *tps;
         struct tracing_data *tdata;
+        int err;
 
         output_fd = fd;
 
@@ -498,13 +550,24 @@ struct tracing_data *tracing_data_get(struct list_head *pattrs,
                 output_fd = temp_fd;
         }
 
-        tracing_data_header();
-        read_header_files();
-        read_ftrace_files(tps);
-        read_event_files(tps);
-        read_proc_kallsyms();
-        read_ftrace_printk();
+        err = tracing_data_header();
+        if (err)
+                goto out;
+        err = read_header_files();
+        if (err)
+                goto out;
+        err = read_ftrace_files(tps);
+        if (err)
+                goto out;
+        err = read_event_files(tps);
+        if (err)
+                goto out;
+        err = read_proc_kallsyms();
+        if (err)
+                goto out;
+        err = read_ftrace_printk();
 
+out:
         /*
          * All tracing data are stored by now, we can restore
          * the default output file in case we used temp file.
@@ -515,22 +578,31 @@ struct tracing_data *tracing_data_get(struct list_head *pattrs,
                 output_fd = fd;
         }
 
+        if (err) {
+                free(tdata);
+                tdata = NULL;
+        }
+
         put_tracepoints_path(tps);
         return tdata;
 }
 
-void tracing_data_put(struct tracing_data *tdata)
+int tracing_data_put(struct tracing_data *tdata)
 {
+        int err = 0;
+
         if (tdata->temp) {
-                record_file(tdata->temp_file, 0);
+                err = record_file(tdata->temp_file, 0);
                 unlink(tdata->temp_file);
         }
 
         free(tdata);
+        return err;
 }
 
 int read_tracing_data(int fd, struct list_head *pattrs)
 {
+        int err;
         struct tracing_data *tdata;
 
         /*
@@ -541,6 +613,6 @@ int read_tracing_data(int fd, struct list_head *pattrs)
         if (!tdata)
                 return -ENOMEM;
 
-        tracing_data_put(tdata);
-        return 0;
+        err = tracing_data_put(tdata);
+        return err;
 }
diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h
index 28ccde8ba20f..1978c398ad87 100644
--- a/tools/perf/util/trace-event.h
+++ b/tools/perf/util/trace-event.h
@@ -68,7 +68,7 @@ struct tracing_data {
 
 struct tracing_data *tracing_data_get(struct list_head *pattrs,
                                       int fd, bool temp);
-void tracing_data_put(struct tracing_data *tdata);
+int tracing_data_put(struct tracing_data *tdata);
 
 
 struct addr_location;