t/helper/test-json-writer.c: avoid using strtok()

Apply similar treatment as in the previous commit to remove usage of
`strtok()` from the "oidmap" test helper.

Each of the different commands that the "json-writer" helper accepts
pops the next space-delimited token from the current line and interprets
it as a string, integer, or double (with the exception of the very first
token, which is the command itself).

To accommodate this, split the line in place by the space character, and
pass the corresponding string_list to each of the specialized `get_s()`,
`get_i()`, and `get_d()` functions.

`get_i()` and `get_d()` are thin wrappers around `get_s()` that convert
their result into the appropriate type by either calling `strtol()` or
`strtod()`, respectively. In `get_s()`, we mark the token as "consumed"
by incrementing the `consumed_nr` counter, indicating how many tokens we
have read up to that point.

Because each of these functions needs the string-list parts, the number
of tokens consumed, and the line number, these three are wrapped up in
to a struct representing the line state.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/helper/test-json-writer.c

@@ -1,5 +1,6 @@
 #include "test-tool.h"
 #include "json-writer.h"
+#include "string-list.h"
 
 static const char *expect_obj1 = "{\"a\":\"abc\",\"b\":42,\"c\":true}";
 static const char *expect_obj2 = "{\"a\":-1,\"b\":2147483647,\"c\":0}";
@@ -394,35 +395,41 @@ static int unit_tests(void)
 	return 0;
 }
 
-static void get_s(int line_nr, char **s_in)
+struct line {
+	struct string_list *parts;
+	size_t consumed_nr;
+	int nr;
+};
+
+static void get_s(struct line *line, char **s_in)
 {
-	*s_in = strtok(NULL, " ");
+	if (line->consumed_nr > line->parts->nr)
-	if (!*s_in)
+		die("line[%d]: expected: <s>", line->nr);
-		die("line[%d]: expected: <s>", line_nr);
+	*s_in = line->parts->items[line->consumed_nr++].string;
 }
 
-static void get_i(int line_nr, intmax_t *s_in)
+static void get_i(struct line *line, intmax_t *s_in)
 {
 	char *s;
 	char *endptr;
 
-	get_s(line_nr, &s);
+	get_s(line, &s);
 
 	*s_in = strtol(s, &endptr, 10);
 	if (*endptr || errno == ERANGE)
-		die("line[%d]: invalid integer value", line_nr);
+		die("line[%d]: invalid integer value", line->nr);
 }
 
-static void get_d(int line_nr, double *s_in)
+static void get_d(struct line *line, double *s_in)
 {
 	char *s;
 	char *endptr;
 
-	get_s(line_nr, &s);
+	get_s(line, &s);
 
 	*s_in = strtod(s, &endptr);
 	if (*endptr || errno == ERANGE)
-		die("line[%d]: invalid float value", line_nr);
+		die("line[%d]: invalid float value", line->nr);
 }
 
 static int pretty;
@@ -453,6 +460,7 @@ static char *get_trimmed_line(char *buf, int buf_size)
 
 static int scripted(void)
 {
+	struct string_list parts = STRING_LIST_INIT_NODUP;
 	struct json_writer jw = JSON_WRITER_INIT;
 	char buf[MAX_LINE_LENGTH];
 	char *line;
@@ -470,66 +478,77 @@ static int scripted(void)
 		die("expected first line to be 'object' or 'array'");
 
 	while ((line = get_trimmed_line(buf, MAX_LINE_LENGTH)) != NULL) {
+		struct line state = { 0 };
 		char *verb;
 		char *key;
 		char *s_value;
 		intmax_t i_value;
 		double d_value;
 
-		line_nr++;
+		state.parts = &parts;
+		state.nr = ++line_nr;
 
-		verb = strtok(line, " ");
+		/* break line into command and zero or more tokens */
+		string_list_setlen(&parts, 0);
+		string_list_split_in_place(&parts, line, " ", -1);
+		string_list_remove_empty_items(&parts, 0);
+
+		/* ignore empty lines */
+		if (!parts.nr || !*parts.items[0].string)
+			continue;
+
+		verb = parts.items[state.consumed_nr++].string;
 
 		if (!strcmp(verb, "end")) {
 			jw_end(&jw);
 		}
 		else if (!strcmp(verb, "object-string")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
-			get_s(line_nr, &s_value);
+			get_s(&state, &s_value);
 			jw_object_string(&jw, key, s_value);
 		}
 		else if (!strcmp(verb, "object-int")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
-			get_i(line_nr, &i_value);
+			get_i(&state, &i_value);
 			jw_object_intmax(&jw, key, i_value);
 		}
 		else if (!strcmp(verb, "object-double")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
-			get_i(line_nr, &i_value);
+			get_i(&state, &i_value);
-			get_d(line_nr, &d_value);
+			get_d(&state, &d_value);
 			jw_object_double(&jw, key, i_value, d_value);
 		}
 		else if (!strcmp(verb, "object-true")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
 			jw_object_true(&jw, key);
 		}
 		else if (!strcmp(verb, "object-false")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
 			jw_object_false(&jw, key);
 		}
 		else if (!strcmp(verb, "object-null")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
 			jw_object_null(&jw, key);
 		}
 		else if (!strcmp(verb, "object-object")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
 			jw_object_inline_begin_object(&jw, key);
 		}
 		else if (!strcmp(verb, "object-array")) {
-			get_s(line_nr, &key);
+			get_s(&state, &key);
 			jw_object_inline_begin_array(&jw, key);
 		}
 		else if (!strcmp(verb, "array-string")) {
-			get_s(line_nr, &s_value);
+			get_s(&state, &s_value);
 			jw_array_string(&jw, s_value);
 		}
 		else if (!strcmp(verb, "array-int")) {
-			get_i(line_nr, &i_value);
+			get_i(&state, &i_value);
 			jw_array_intmax(&jw, i_value);
 		}
 		else if (!strcmp(verb, "array-double")) {
-			get_i(line_nr, &i_value);
+			get_i(&state, &i_value);
-			get_d(line_nr, &d_value);
+			get_d(&state, &d_value);
 			jw_array_double(&jw, i_value, d_value);
 		}
 		else if (!strcmp(verb, "array-true"))
@@ -552,6 +571,7 @@ static int scripted(void)
 	printf("%s\n", jw.json.buf);
 
 	jw_release(&jw);
+	string_list_clear(&parts, 0);
 	return 0;
 }