[PATCH v3] parser: be more picky for integer values

[Tiago Vignatti]

It was silently accepting "-i=3", "-i=3/2", "--idle-time=*3" and similar
unwanted type of arguments, not changing anything internally; this
gives the wrong impression for the user. Now it explicitly warns.

Signed-off-by: Tiago Vignatti <tiago.vignatti at intel.com>
---
Pekka, I guess now it's alright, please take a look. If it's good to go, you
would mind to stamp a Reviewed-By for the other patches in this series as
well?

Thank you.

since v2:
- adjusted to the correct limits based on stdint.h
- instead drastically assert(0) on illegal user input, now it returns a
  warning message and continue the execution of the program.

 shared/option-parser.c |   57 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/shared/option-parser.c b/shared/option-parser.c
index 600f110..0e607d9 100644
--- a/shared/option-parser.c
+++ b/shared/option-parser.c
@@ -25,18 +25,71 @@
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>
+#include <limits.h>
+#include <errno.h>
 
 #include "config-parser.h"
 
+static int
+get_int(void *ret, const char *value)
+{
+	char *end;
+	long int v;
+
+	errno = 0;
+	v = strtol(value, &end, 0);
+	if ((errno == ERANGE && (v == LONG_MAX || v == LONG_MIN)) ||
+	    (errno != 0 && v == 0) ||
+	    (end == value) ||
+	    (*end != '\0')) {
+		fprintf(stderr, "arg %s is not a valid number\n", value);
+		return -1;
+	}
+
+	if (v < INT32_MIN || v > INT32_MAX) {
+		fprintf(stderr, "arg %s doesn't fit into integer\n", value);
+		return -1;
+	}
+
+	* (int32_t *) ret = v;
+	return 1;
+}
+
+static int
+get_uint(void *ret, const char *value)
+{
+	char *end;
+	long int v;
+
+	errno = 0;
+	v = strtol(value, &end, 0);
+	if ((errno == ERANGE && (v == ULONG_MAX)) ||
+	    (errno != 0 && v == 0) ||
+	    (end == value) ||
+	    (*end != '\0')) {
+		fprintf(stderr, "arg %s is not a valid number\n", value);
+		return -1;
+	}
+
+	if (v < 0 || v > UINT32_MAX) {
+		fprintf(stderr, "arg %s doesn't fit into unsigned integer\n",
+			value);
+		return -1;
+	}
+
+	* (uint32_t *) ret = v;
+	return 1;
+}
+
 static void
 handle_option(const struct weston_option *option, char *value)
 {
 	switch (option->type) {
 	case WESTON_OPTION_INTEGER:
-		* (int32_t *) option->data = strtol(value, NULL, 0);
+		get_int(option->data, value);
 		return;
 	case WESTON_OPTION_UNSIGNED_INTEGER:
-		* (uint32_t *) option->data = strtoul(value, NULL, 0);
+		get_uint(option->data, value);
 		return;
 	case WESTON_OPTION_STRING:
 		* (char **) option->data = strdup(value);
-- 
1.7.5.4