Coverity scan findings - memleaks, unused vars, potential nullptr dereferences

lib/test_process.c

@@ -69,6 +69,7 @@ signal_handler(int signum, siginfo_t *siginfo, void *ucontext)
 	    exit(EXIT_FAILURE);
     }
 
+    free(signame);
 }
 
 int main(int argc, char *argv[])

pmap.c

@@ -352,6 +352,9 @@ static void print_extended_maps (FILE *f)
 			if (listnode == NULL) {
 				assert(firstmapping == 2);
 				listnode = calloc(1, sizeof *listnode);
+				if (listnode == NULL)
+					xerrx(EXIT_FAILURE, _("ERROR: memory allocation failed"));
+
 				if (listhead == NULL) {
 					assert(listtail == NULL);
 					listhead = listnode;

watch.c

@@ -125,8 +125,6 @@ static void reset_ansi(void)
 
 static void init_ansi_colors(void)
 {
-	int color;
-
 	short ncurses_colors[] = {
 		-1, COLOR_BLACK, COLOR_RED, COLOR_GREEN, COLOR_YELLOW,
 		COLOR_BLUE, COLOR_MAGENTA, COLOR_CYAN, COLOR_WHITE
@@ -173,6 +171,9 @@ static int process_ansi_color_escape_sequence(char** escape_sequence) {
 	// ESC[ 48;2;⟨r⟩;⟨g⟩;⟨b⟩ m Select RGB background color
 	int num;
 
+	if (!escape_sequence)
+		return 0; /* avoid NULLPTR dereference, return "not understood" */
+
 	if ((*escape_sequence)[0] != ';')
 		return 0; /* not understood */