[PATCH perf/core v3 4/8] perf: Make alias handler to check return value of strbuf

From: Masami Hiramatsu
Date: Tue May 10 2016 - 01:47:35 EST


Make alias handler and sq_quote_argv to check the return
value of strbuf APIs.
In sq_quote_argv() calls die(), but this fix handles strbuf
failure as a special case and returns to caller, since
the caller - handle_alias() also has to check the return
value of other strbuf APIs and those checks can be merged
to one if() statement.

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
tools/perf/perf.c | 8 +++++---
tools/perf/util/quote.c | 36 ++++++++++++++++++++----------------
tools/perf/util/quote.h | 2 +-
3 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 83ffe7c..7970008 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -309,9 +309,11 @@ static int handle_alias(int *argcp, const char ***argv)
if (*argcp > 1) {
struct strbuf buf;

- strbuf_init(&buf, PATH_MAX);
- strbuf_addstr(&buf, alias_string);
- sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
+ if (strbuf_init(&buf, PATH_MAX) < 0 ||
+ strbuf_addstr(&buf, alias_string) < 0 ||
+ sq_quote_argv(&buf, (*argv) + 1,
+ PATH_MAX) < 0)
+ die("Failed to allocate memory.");
free(alias_string);
alias_string = buf.buf;
}
diff --git a/tools/perf/util/quote.c b/tools/perf/util/quote.c
index 01f0324..c6d4ee2 100644
--- a/tools/perf/util/quote.c
+++ b/tools/perf/util/quote.c
@@ -17,38 +17,42 @@ static inline int need_bs_quote(char c)
return (c == '\'' || c == '!');
}

-static void sq_quote_buf(struct strbuf *dst, const char *src)
+static int sq_quote_buf(struct strbuf *dst, const char *src)
{
char *to_free = NULL;
+ int ret;

if (dst->buf == src)
to_free = strbuf_detach(dst, NULL);

- strbuf_addch(dst, '\'');
- while (*src) {
+ ret = strbuf_addch(dst, '\'');
+ while (!ret && *src) {
size_t len = strcspn(src, "'!");
- strbuf_add(dst, src, len);
+ ret = strbuf_add(dst, src, len);
src += len;
- while (need_bs_quote(*src)) {
- strbuf_addstr(dst, "'\\");
- strbuf_addch(dst, *src++);
- strbuf_addch(dst, '\'');
- }
+ while (!ret && need_bs_quote(*src))
+ ret = strbuf_addf(dst, "'\\%c\'", *src++);
}
- strbuf_addch(dst, '\'');
+ if (!ret)
+ ret = strbuf_addch(dst, '\'');
free(to_free);
+
+ return ret;
}

-void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
+int sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
{
- int i;
+ int i, ret;

/* Copy into destination buffer. */
- strbuf_grow(dst, 255);
- for (i = 0; argv[i]; ++i) {
- strbuf_addch(dst, ' ');
- sq_quote_buf(dst, argv[i]);
+ ret = strbuf_grow(dst, 255);
+ for (i = 0; !ret && argv[i]; ++i) {
+ ret = strbuf_addch(dst, ' ');
+ if (ret)
+ break;
+ ret = sq_quote_buf(dst, argv[i]);
if (maxlen && dst->len > maxlen)
die("Too many or long arguments");
}
+ return ret;
}
diff --git a/tools/perf/util/quote.h b/tools/perf/util/quote.h
index 3340c9c..e1ec191 100644
--- a/tools/perf/util/quote.h
+++ b/tools/perf/util/quote.h
@@ -24,6 +24,6 @@
* sq_quote() in a real application.
*/

-void sq_quote_argv(struct strbuf *, const char **argv, size_t maxlen);
+int sq_quote_argv(struct strbuf *, const char **argv, size_t maxlen);

#endif /* __PERF_QUOTE_H */