Replace atoi() with strtol() which allows error checking

atoi() gives no opportunity for error checking, strtol() does. Improved
error checking.

Closes #1422

libusb/core.c

@@ -2380,14 +2380,19 @@ int API_EXPORTEDV libusb_set_option(libusb_context *ctx,
  */
 static enum libusb_log_level get_env_debug_level(void)
 {
+	enum libusb_log_level level = LIBUSB_LOG_LEVEL_NONE;
 	const char *dbg = getenv("LIBUSB_DEBUG");
-	enum libusb_log_level level;
 	if (dbg) {
-		int dbg_level = atoi(dbg);
+		char *end = NULL;
+		long dbg_level = strtol(dbg, &end, 10);
+		if (dbg == end ||
+			*end != '\0' ||
+			dbg_level < LIBUSB_LOG_LEVEL_NONE ||
+			dbg_level > LIBUSB_LOG_LEVEL_DEBUG) {
+			usbi_warn(NULL, "LIBUSB_DEBUG is invalid or out of range; clamping");
+		}
 		dbg_level = CLAMP(dbg_level, LIBUSB_LOG_LEVEL_NONE, LIBUSB_LOG_LEVEL_DEBUG);
 		level = (enum libusb_log_level)dbg_level;
-	} else {
-		level = LIBUSB_LOG_LEVEL_NONE;
 	}
 	return level;
 }

libusb/os/linux_usbfs.c

@@ -541,7 +541,7 @@ static int read_sysfs_attr(struct libusb_context *ctx,
 
 	errno = 0;
 	value = strtol(buf, &endptr, 10);
-	if (value < 0 || value > (long)max_value || errno) {
+	if (buf == endptr || value < 0 || value > (long)max_value || errno) {
 		usbi_err(ctx, "attribute %s contains an invalid value: '%s'", attr, buf);
 		return LIBUSB_ERROR_INVALID_PARAM;
 	} else if (*endptr != '\0') {
@@ -1033,7 +1033,7 @@ static int linux_get_parent_info(struct libusb_device *dev, const char *sysfs_di
 {
 	struct libusb_context *ctx = DEVICE_CTX(dev);
 	struct libusb_device *it;
-	char *parent_sysfs_dir, *tmp;
+	char *parent_sysfs_dir, *tmp, *end;
 	int ret, add_parent = 1;
 
 	/* XXX -- can we figure out the topology when using usbfs? */
@@ -1048,7 +1048,16 @@ static int linux_get_parent_info(struct libusb_device *dev, const char *sysfs_di
 
 	if ((tmp = strrchr(parent_sysfs_dir, '.')) ||
 	    (tmp = strrchr(parent_sysfs_dir, '-'))) {
-	        dev->port_number = atoi(tmp + 1);
+		const char *start = tmp + 1;
+		long port_number = strtol(start, &end, 10);
+		if (port_number < 0 || port_number > INT_MAX || start == end || '\0' != *end) {
+			usbi_warn(ctx, "Can not parse sysfs_dir: %s, unexpected parent info",
+				parent_sysfs_dir);
+			free(parent_sysfs_dir);
+			return LIBUSB_ERROR_OTHER;
+		} else {
+			dev->port_number = (int)port_number;
+		}
 		*tmp = '\0';
 	} else {
 		usbi_warn(ctx, "Can not parse sysfs_dir: %s, no parent info",

libusb/os/windows_winusb.c

@@ -29,6 +29,7 @@
 #include <setupapi.h>
 #include <ctype.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "libusbi.h"
 #include "windows_winusb.h"
@@ -1229,6 +1230,9 @@ static bool get_dev_port_number(HDEVINFO dev_info, SP_DEVINFO_DATA *dev_info_dat
 {
 	char buffer[MAX_KEY_LENGTH];
 	DWORD size;
+	const char *start = NULL;
+	char *end = NULL;
+	long long port;
 
 	// First try SPDRP_LOCATION_INFORMATION, which returns a REG_SZ. The string *may* have a format
 	// similar to "Port_#0002.Hub_#000D", in which case we can extract the port number. However, we
@@ -1237,7 +1241,12 @@ static bool get_dev_port_number(HDEVINFO dev_info, SP_DEVINFO_DATA *dev_info_dat
 			NULL, (PBYTE)buffer, sizeof(buffer), NULL)) {
 		// Check for the required format.
 		if (strncmp(buffer, "Port_#", 6) == 0) {
-			*port_nr = atoi(buffer + 6);
+			start = buffer + 6;
+			port = strtoll(start, &end, 10);
+			if (port < 0 || port > ULONG_MAX || end == start || *end != '\0') {
+				return false;
+			}
+			*port_nr = (DWORD)port;
 			return true;
 		}
 	}
@@ -1251,7 +1260,12 @@ static bool get_dev_port_number(HDEVINFO dev_info, SP_DEVINFO_DATA *dev_info_dat
 		// Find the last "#USB(x)" substring
 		for (char *token = strrchr(buffer, '#'); token != NULL; token = strrchr(buffer, '#')) {
 			if (strncmp(token, "#USB(", 5) == 0) {
-				*port_nr = atoi(token + 5);
+				start = token + 5;
+				port = strtoll(start, &end, 10);
+				if (port < 0 || port > ULONG_MAX || end == start || *end != '\0') {
+					return false;
+				}
+				*port_nr = (DWORD)port;
 				return true;
 			}
 			// Shorten the string and try again.

libusb/version_nano.h

@@ -1 +1 @@
-#define LIBUSB_NANO 11928
+#define LIBUSB_NANO 11929