builtin: do not use unsafe sprintf/vsprintf functions

vlib/builtin/builtin.v

@@ -195,28 +195,3 @@ pub fn is_atty(fd int) int {
 		return C.isatty(fd)
 	}
 }
-
-/*
-fn C.va_start()
-fn C.va_end()
-fn C.vsnprintf() int
-fn C.vsprintf() int
-
-pub fn str2_(fmt charptr, ...) string {
-       argptr := C.va_list{}
-        C.va_start(argptr, fmt)
-        len := C.vsnprintf(0, 0, fmt, argptr) + 1
-C.va_end(argptr)
-        buf := malloc(len)
-        C.va_start(argptr, fmt)
-        C.vsprintf(charptr(buf), fmt, argptr)
-        C.va_end(argptr)
-//#ifdef DEBUG_ALLOC
-//        puts("_STR:");
-//        puts(buf);
-//#endif
-        return tos2(buf)
-}
-*/
-
-

vlib/compiler/live.v

@@ -110,24 +110,35 @@ fn (v &V) generate_hot_reload_code() {
 		cgen.genln('
 
 void lfnmutex_print(char *s){
-	if(0){
+#if 0
-		fflush(stderr);
+	fflush(stderr);
-		fprintf(stderr,">> live_fn_mutex: %p | %s\\n", &live_fn_mutex, s);
+	fprintf(stderr,">> live_fn_mutex: %p | %s\\n", &live_fn_mutex, s);
-		fflush(stderr);
+	fflush(stderr);
-	}
+#endif
 }
 ')
 		if v.pref.os != .windows {
 			cgen.genln('
-void* live_lib=0;
+#define _POSIX_C_SOURCE 1
+#include <limits.h>
+#ifndef PATH_MAX
+#define PATH_MAX 1024
+#endif
+
+void* live_lib = 0;
+
 int load_so(byteptr path) {
-	char cpath[1024];
+	char cpath[PATH_MAX] = {0};
-	sprintf(cpath,"./%s", path);
+	int res = snprintf(cpath, sizeof (cpath), "./%s", path);
+	if (res >= sizeof (cpath)) {
+		fprintf (stderr, "path is too long");
+		return 0;
+	}
 	//printf("load_so %s\\n", cpath);
 	if (live_lib) dlclose(live_lib);
 	live_lib = dlopen(cpath, RTLD_LAZY);
 	if (!live_lib) {
-		puts("open failed");
+		fprintf(stderr, "open failed");
 		exit(1);
 		return 0;
 	}
@@ -138,6 +149,11 @@ int load_so(byteptr path) {
 		}
 		else {
 			cgen.genln('
+
+#ifndef PATH_MAX
+#define PATH_MAX 1024
+#endif
+
 void pthread_mutex_lock(HANDLE *m) {
 	WaitForSingleObject(*m, INFINITE);
 }
@@ -146,14 +162,19 @@ void pthread_mutex_unlock(HANDLE *m) {
 	ReleaseMutex(*m);
 }
 
-void* live_lib=0;
+void* live_lib = NULL;
 int load_so(byteptr path) {
-	char cpath[1024];
+	char cpath[PATH_MAX];
-	sprintf(cpath, "./%s", path);
+	int res = snprintf(cpath, sizeof (cpath), "./%s", path);
+	if (res >= sizeof(cpath)) {
+		puts("path is too long\\n");
+		exit(1);
+		return 0;
+	}
 	if (live_lib) FreeLibrary(live_lib);
 	live_lib = LoadLibraryA(cpath);
 	if (!live_lib) {
-		puts("open failed");
+		puts("open failed\\n");
 		exit(1);
 		return 0;
 	}
@@ -167,9 +188,9 @@ int load_so(byteptr path) {
 
 int _live_reloads = 0;
 void reload_so() {
-	char new_so_base[1024];
+	char new_so_base[PATH_MAX] = {0};
-	char new_so_name[1024];
+	char new_so_name[PATH_MAX] = {0};
-	char compile_cmd[1024];
+	char compile_cmd[PATH_MAX] = {0};
 	int last = os__file_last_mod_unix(tos2("$file"));
 	while (1) {
 		// TODO use inotify
@@ -179,22 +200,22 @@ void reload_so() {
 			_live_reloads++;
 
 			//v -o bounce -shared bounce.v
-			sprintf(new_so_base, ".tmp.%d.${file_base}", _live_reloads);
+			snprintf(new_so_base, sizeof (new_so_base), ".tmp.%d.${file_base}", _live_reloads);
 			#ifdef _WIN32
 			// We have to make this directory becuase windows WILL NOT
 			// do it for us
 			os__mkdir(string_all_before_last(tos2(new_so_base), tos2("/")));
 			#endif
 			#ifdef _MSC_VER
-			sprintf(new_so_name, "%s.dll", new_so_base);
+			snprintf(new_so_name, sizeof (new_so_name), "%s.dll", new_so_base);
 			#else
-			sprintf(new_so_name, "%s.so", new_so_base);
+			snprintf(new_so_name, sizeof (new_so_name), "%s.so", new_so_base);
 			#endif
-			sprintf(compile_cmd, "$vexe $msvc -o %s -solive -shared $file", new_so_base);
+			snprintf(compile_cmd, sizeof (compile_cmd), "$vexe $msvc -o %s -solive -shared $file", new_so_base);
 			os__system(tos2(compile_cmd));
 
 			if( !os__exists(tos2(new_so_name)) ) {
-				fprintf(stderr, "Errors while compiling $file\\n");
+				puts("Errors while compiling $file\\n");
 				continue;
 			}
 

vlib/compiler/tests/live_test.v

@@ -0,0 +1,97 @@
+import os
+import time
+
+const (
+	vexe = os.getenv('VEXE')
+	source_file = os.join_path(os.temp_dir(), 'generated_live_program.v')
+	output_file = os.join_path(os.temp_dir(), 'generated_live_program.output.txt')
+	live_program_source = "
+module main
+import time
+
+[live]
+fn pmessage() {
+	println('ORIGINAL')
+}
+
+fn main() {
+	println('START')
+	for i := 0; i<6*100; i++ {
+		pmessage()
+		time.sleep_ms(10)
+	}
+	println('END')
+}
+"
+)
+
+//
+
+fn testsuite_begin(){
+	if os.user_os() != 'linux' && os.getenv('FORCE_LIVE_TEST').len == 0 {
+		eprintln('Testing the runtime behaviour of -live mode,')
+		eprintln('is reliable only on Linux for now.')
+		eprintln('You can still do it by setting FORCE_LIVE_TEST=1 .')
+		exit(0)
+	}
+	os.write_file(source_file, live_program_source)
+}
+
+fn testsuite_end(){
+	os.rm( source_file )
+	eprintln('source: $source_file')
+	eprintln('output: $output_file')
+	$if !windows {
+		os.system('cat $output_file')
+	}
+	println('---------------------------------------------------------------------------')
+	output_lines := os.read_lines( output_file ) or {
+		return
+	}
+	mut histogram := map[string]int
+	for line in output_lines {
+		histogram[line] = histogram[line] + 1
+	}
+	for k,v in histogram {
+		println('> found ${k} $v times.')
+	}
+	println('---------------------------------------------------------------------------')
+	assert histogram['START'] > 0
+	assert histogram['END'] > 0
+	assert histogram['CHANGED'] + histogram['ANOTHER'] > 0
+	assert histogram['ORIGINAL'] > 0
+}
+
+fn change_source(new string){
+	time.sleep_ms(250)
+	eprintln('> change ORIGINAL to: $new')
+	os.write_file(source_file,live_program_source.replace('ORIGINAL', new))
+	time.sleep_ms(1000)
+	eprintln('> done.')
+}
+
+//
+
+fn test_live_program_can_be_compiled(){
+	cmd := '$vexe -live run $source_file > $output_file &'
+	eprintln('Compiling and running with: $cmd')
+	res := os.system(cmd)
+	eprintln('... running in the background')
+	time.sleep_ms(3000)
+	assert res == 0
+}
+
+fn test_live_program_can_be_changed_1(){
+	change_source('CHANGED')
+	assert true
+}
+
+fn test_live_program_can_be_changed_2(){
+	change_source('ANOTHER')
+	assert true
+}
+
+fn test_live_program_has_ended(){
+	time.sleep_ms(10*1000)
+	assert true
+}

vlib/time/parse.v

@@ -42,7 +42,7 @@ pub fn parse_rfc2822(s string) ?Time {
 	mm := pos / 3 + 1
 	mut tmstr := byteptr(0)
 	unsafe { tmstr = malloc(s.len * 2) }
-	count := C.sprintf(charptr(tmstr), '%s-%02d-%s %s', fields[3].str, mm,
+	count := C.snprintf(charptr(tmstr), (s.len *  2), '%s-%02d-%s %s', fields[3].str, mm,
 		fields[1].str, fields[4].str)
 
 	t := parse(tos(tmstr, count)) or {