all: Use internal MEMMEM instead gnu memem

It is used only on small strings, so it is fast enough

src/global.h

@@ -24,4 +24,17 @@ extern int verbose;
 
 #define SLEEP(usec) do { struct timespec _t = { 0, (usec) }; nanosleep(&_t, NULL); } while (0)
 
+static inline void * MEMMEM(void *haystack, size_t haystacklen, const void *needle, size_t needlelen) {
+	for ( size_t i = 0; i < haystacklen; ++i ) {
+		for ( size_t j = 0; j < needlelen; ++j ) {
+			if ( ((char *)haystack)[i] != ((const char *)needle)[j] )
+				break;
+			if ( j != needlelen - 1 )
+				continue;
+			return (char *)haystack + i;
+		}
+	}
+	return NULL;
+}
+
 #endif

src/mkii.c

@@ -262,7 +262,7 @@ int mkii_flash_image(struct usb_device_info * dev, struct image * image) {
 
 			for ( i = 0; bufs[i]; ++i ) {
 				len = ((uint8_t*)bufs[i])[0];
-				if ( memmem(bufs[i]+1, len, buf, strlen(buf)) )
+				if ( MEMMEM(bufs[i]+1, len, buf, strlen(buf)) )
 					break;
 			}
 

src/nolo.c

@@ -127,7 +127,7 @@ static int nolo_identify_string(struct usb_device_info * dev, const char * str,
 	if ( (size_t)ret > sizeof(buf) )
 		ret = sizeof(buf);
 
-	ptr = memmem(buf, ret, str, strlen(str));
+	ptr = MEMMEM(buf, ret, str, strlen(str));
 	if ( ! ptr )
 		ERROR_RETURN("Substring was not found", -1);
 
@@ -326,7 +326,7 @@ static int nolo_send_image(struct usb_device_info * dev, struct image * image, i
 
 			for ( i = 0; bufs[i]; ++i ) {
 				len = ((uint8_t*)bufs[i])[0];
-				if ( memmem(bufs[i]+1, len, buf, strlen(buf)) )
+				if ( MEMMEM(bufs[i]+1, len, buf, strlen(buf)) )
 					break;
 			}