perf probe: Rewrite find_lazy_match_lines() by using getline(3)

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: lkml <linux-kernel@vger.kernel.org>
LKML-Reference: <m3d3o185u1.fsf@gmail.com>
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 28 insertions, 44 deletions

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 69215bff17e9..46addfb3183e 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -1234,51 +1234,38 @@ static int find_probe_point_by_line(struct probe_finder *pf)
 static int find_lazy_match_lines(struct list_head *head,
                                  const char *fname, const char *pat)
 {
-        char *fbuf, *p1, *p2;
-        int fd, line, nlines = -1;
-        struct stat st;
-
-        fd = open(fname, O_RDONLY);
-        if (fd < 0) {
-                pr_warning("Failed to open %s: %s\n", fname, strerror(-fd));
+        FILE *fp;
+        char *line = NULL;
+        size_t line_len;
+        ssize_t len;
+        int count = 0, linenum = 1;
+
+        fp = fopen(fname, "r");
+        if (!fp) {
+                pr_warning("Failed to open %s: %s\n", fname, strerror(errno));
                 return -errno;
         }
 
-        if (fstat(fd, &st) < 0) {
-                pr_warning("Failed to get the size of %s: %s\n",
-                           fname, strerror(errno));
-                nlines = -errno;
-                goto out_close;
-        }
-
-        nlines = -ENOMEM;
-        fbuf = malloc(st.st_size + 2);
-        if (fbuf == NULL)
-                goto out_close;
-        if (read(fd, fbuf, st.st_size) < 0) {
-                pr_warning("Failed to read %s: %s\n", fname, strerror(errno));
-                nlines = -errno;
-                goto out_free_fbuf;
-        }
-        fbuf[st.st_size] = '\n';        /* Dummy line */
-        fbuf[st.st_size + 1] = '\0';
-        p1 = fbuf;
-        line = 1;
-        nlines = 0;
-        while ((p2 = strchr(p1, '\n')) != NULL) {
-                *p2 = '\0';
-                if (strlazymatch(p1, pat)) {
-                        line_list__add_line(head, line);
-                        nlines++;
+        while ((len = getline(&line, &line_len, fp)) > 0) {
+
+                if (line[len - 1] == '\n')
+                        line[len - 1] = '\0';
+
+                if (strlazymatch(line, pat)) {
+                        line_list__add_line(head, linenum);
+                        count++;
                 }
-                line++;
-                p1 = p2 + 1;
+                linenum++;
         }
-out_free_fbuf:
-        free(fbuf);
-out_close:
-        close(fd);
-        return nlines;
+
+        if (ferror(fp))
+                count = -errno;
+        free(line);
+        fclose(fp);
+
+        if (count == 0)
+                pr_debug("No matched lines found in %s.\n", fname);
+        return count;
 }
 
 static int probe_point_lazy_walker(const char *fname, int lineno,
@@ -1312,10 +1299,7 @@ static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
                 /* Matching lazy line pattern */
                 ret = find_lazy_match_lines(&pf->lcache, pf->fname,
                                             pf->pev->point.lazy_line);
-                if (ret == 0) {
-                        pr_debug("No matched lines found in %s.\n", pf->fname);
-                        return 0;
-                } else if (ret < 0)
+                if (ret <= 0)
                         return ret;
         }