1 files changed, 45 insertions, 44 deletions

diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
index 7cd1193918c7..44889c9b5630 100644
--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c
@@ -50,14 +50,37 @@ static int long_size;
 
 static unsigned long    page_size;
 
+static ssize_t calc_data_size;
+
+static int do_read(int fd, void *buf, int size)
+{
+        int rsize = size;
+
+        while (size) {
+                int ret = read(fd, buf, size);
+
+                if (ret <= 0)
+                        return -1;
+
+                size -= ret;
+                buf += ret;
+        }
+
+        return rsize;
+}
+
 static int read_or_die(void *data, int size)
 {
         int r;
 
-        r = read(input_fd, data, size);
-        if (r != size)
+        r = do_read(input_fd, data, size);
+        if (r <= 0)
                 die("reading input file (size expected=%d received=%d)",
                     size, r);
+
+        if (calc_data_size)
+                calc_data_size += r;
+
         return r;
 }
 
@@ -82,56 +105,28 @@ static char *read_string(void)
         char buf[BUFSIZ];
         char *str = NULL;
         int size = 0;
-        int i;
         off_t r;
+        char c;
 
         for (;;) {
-                r = read(input_fd, buf, BUFSIZ);
+                r = read(input_fd, &c, 1);
                 if (r < 0)
                         die("reading input file");
 
                 if (!r)
                         die("no data");
 
-                for (i = 0; i < r; i++) {
-                        if (!buf[i])
-                                break;
-                }
-                if (i < r)
-                        break;
+                buf[size++] = c;
 
-                if (str) {
-                        size += BUFSIZ;
-                        str = realloc(str, size);
-                        if (!str)
-                                die("malloc of size %d", size);
-                        memcpy(str + (size - BUFSIZ), buf, BUFSIZ);
-                } else {
-                        size = BUFSIZ;
-                        str = malloc_or_die(size);
-                        memcpy(str, buf, size);
-                }
+                if (!c)
+                        break;
         }
 
-        /* trailing \0: */
-        i++;
-
-        /* move the file descriptor to the end of the string */
-        r = lseek(input_fd, -(r - i), SEEK_CUR);
-        if (r == (off_t)-1)
-                die("lseek");
-
-        if (str) {
-                size += i;
-                str = realloc(str, size);
-                if (!str)
-                        die("malloc of size %d", size);
-                memcpy(str + (size - i), buf, i);
-        } else {
-                size = i;
-                str = malloc_or_die(i);
-                memcpy(str, buf, i);
-        }
+        if (calc_data_size)
+                calc_data_size += size;
+
+        str = malloc_or_die(size);
+        memcpy(str, buf, size);
 
         return str;
 }
@@ -459,7 +454,7 @@ struct record *trace_read_data(int cpu)
         return data;
 }
 
-void trace_report(int fd)
+ssize_t trace_report(int fd)
 {
         char buf[BUFSIZ];
         char test[] = { 23, 8, 68 };
@@ -467,6 +462,9 @@ void trace_report(int fd)
         int show_version = 0;
         int show_funcs = 0;
         int show_printk = 0;
+        ssize_t size;
+
+        calc_data_size = 1;
 
         input_fd = fd;
 
@@ -499,14 +497,17 @@ void trace_report(int fd)
         read_proc_kallsyms();
         read_ftrace_printk();
 
+        size = calc_data_size - 1;
+        calc_data_size = 0;
+
         if (show_funcs) {
                 print_funcs();
-                return;
+                return size;
         }
         if (show_printk) {
                 print_printk();
-                return;
+                return size;
         }
 
-        return;
+        return size;
 }