Combined one-letter options support (eg. "-mhp 3")

2 files changed, 120 insertions, 48 deletions

diff --git a/config-parser.c b/config-parser.c
index 3cebc73..0ef0a47 100644
--- a/config-parser.c
+++ b/config-parser.c
@@ -22,27 +22,13 @@ Result parse_config(int argc, char* argv[]) {
 	size_t i = 1;
 	char* argument;
 	char* precision = NULL;
+	bool next_is_precision = false;
 	while (i < argc) {
 		argument = argv[i];
-		int comp1 = strcmp(argument, "--precision") == 0;
-		if (
-			strcmp(argument, "--help") == 0
-			|| strcmp(argument, "-?") == 0
-		) {
-			tmp.help = true;
-		} else if (
-			strcmp(argument, "--human-readable") == 0
-			|| strcmp(argument, "-h") == 0
-		) {
-			tmp.human_readable = true;
-		} else if (
-			strcmp(argument, "--multiline") == 0
-			|| strcmp(argument, "-m") == 0
-		) {
-			tmp.multiline = true;
-		} else if (
-			comp1 || strncmp(argument, "-p", 2) == 0
-		) {
+		size_t arglen = strlen(argument);
+
+		if (next_is_precision) {
+			i += 1;
 			if (precision != NULL) {
 				char* error_msg = malloc(44);
 				snprintf(
@@ -53,11 +39,6 @@ Result parse_config(int argc, char* argv[]) {
 				res.result = error_msg;
 				return res;
 			}
-			i++;
-			if (strlen(argument) != 2 && !comp1) {
-				precision = argument + 2;
-				continue;
-			}
 			if (i == argc) {
 				char* error_msg = malloc(57);
 				snprintf(
@@ -69,21 +50,98 @@ Result parse_config(int argc, char* argv[]) {
 				res.result = error_msg;
 				return res;
 			}
-			precision = argv[i];
-		} else {
-			size_t msg_size = 21 + strlen(argument);
-			char* error_msg = malloc(msg_size);
-			snprintf(
-				error_msg,
-				msg_size,
-				"unknown argument: `%s`",
-				argument
-			);
-			res.result = error_msg;
-			return res;
+			precision = argv[i++];
+			next_is_precision = false;
+			continue;
+		}
+
+		size_t tacktacklen = 2;
+		if (strncmp(argument, "--", tacktacklen) == 0) {
+			argument += tacktacklen;
+			if (strcmp(argument, "help") == 0) {
+				tmp.help = true;
+			} else if (strcmp(argument, "human-readable") == 0) {
+				tmp.human_readable = true;
+			} else if (strcmp(argument, "multiline") == 0) {
+				tmp.multiline = true;
+			} else if (strcmp(argument, "precision") == 0) {
+				next_is_precision = true;
+				continue;
+			} else {
+				argument -= tacktacklen;
+				size_t msg_size = 18 + strlen(argument);
+				char* error_msg = malloc(msg_size);
+				snprintf(
+					error_msg,
+					msg_size,
+					"unknown option `%s`",
+					argument
+				);
+				res.result = error_msg;
+				return res;
+			}
+			i++;
+			continue;
+		}
+
+		if (strncmp(argument, "-p", 2) == 0 && arglen != 2) {
+			if (precision != NULL) {
+				char* error_msg = malloc(44);
+				snprintf(
+					error_msg,
+					44,
+					"precision can't be specified multiple times"
+				);
+				res.result = error_msg;
+				return res;
+			}
+			precision = argument + 2;
+			i++;
+			continue;
 		}
 
-		i++;
+		size_t opt_i = 0;
+		while (++opt_i < arglen) {
+			char opt = *(argument + opt_i);
+			switch (opt) {
+				case 'h':
+					tmp.human_readable = true;
+					break;
+				case 'm':
+					tmp.multiline = true;
+					break;
+				case 'p':
+					next_is_precision = true;
+					if (opt_i != arglen - 1) {
+						size_t msg_size = 75;
+						char* error_msg
+							= malloc(msg_size);
+						snprintf(
+							error_msg,
+							msg_size,
+							"`-p` should be the last option when combined with other one-letter options"
+						);
+						res.result = error_msg;
+						return res;
+					}
+					break;
+				case '?':
+					tmp.help = true;
+					break;
+				default:
+					size_t msg_size = 20;
+					char* error_msg = malloc(msg_size);
+					snprintf(
+						error_msg,
+						msg_size,
+						"unknown option `-%c`",
+						opt
+					);
+					res.result = error_msg;
+					return res;
+			}
+		}
+		i += !next_is_precision;
 	}
 
 	if (precision != NULL) {
@@ -143,8 +201,10 @@ char* test_default_config() {
 	Result res = parse_config(argc, argv);
 	Config* conf = (Config*) res.result;
 	mt_assert_eq(res.success, true);
-	mt_assert_eq(conf->precision, 0);
 	mt_assert_eq(conf->human_readable, false);
+	mt_assert_eq(conf->help, false);
+	mt_assert_eq(conf->multiline, false);
+	mt_assert_eq(conf->precision, 0);
 	free(conf);
 	return 0;
 }
@@ -196,17 +256,28 @@ char* test_human_readability_parsing() {
 	res = parse_config(argc, argv);
 	conf = (Config*) res.result;
 	mt_assert_eq(res.success, true);
-	mt_assert_eq(conf->precision, 0);
 	mt_assert_eq(conf->human_readable, true);
 	free(conf);
 
-	argc = 3;
-	char* argv2[] = { "stdu", "-h", "-h" };
-	res = parse_config(argc, argv2);
-	error_msg = (char*) res.result;
-	mt_assert_eq(res.success, false);
-	free(error_msg);
-	
+	return 0;
+}
+
+char* test_multioption_parsing() {
+	Result res;
+	Config* conf;
+	char* error_msg;
+
+	int argc = 3;
+	char* argv[] = { "stdu", "-mh?p", "3"};
+	res = parse_config(argc, argv);
+	conf = (Config*) res.result;
+	mt_assert_eq(res.success, true);
+	mt_assert_eq(conf->help, true);
+	mt_assert_eq(conf->human_readable, true);
+	mt_assert_eq(conf->multiline, true);
+	mt_assert_eq(conf->precision, 3);
+	free(conf);
+
 	return 0;
 }
 
@@ -214,4 +285,5 @@ void parsing_tests() {
 	mt_run_test(test_default_config);
 	mt_run_test(test_precision_parsing);
 	mt_run_test(test_human_readability_parsing);
+	mt_run_test(test_multioption_parsing);
 }
diff --git a/stdu.c b/stdu.c
index 0c3c7a6..a41071a 100644
--- a/stdu.c
+++ b/stdu.c
@@ -19,7 +19,7 @@ int main (int argc, char* argv[]) {
 		char* err_msg = (char*) res.result;
 		fprintf(
 			stderr,
-			"Error parsing command line: %s\n",
+			"Error parsing command line: %s.\nTry `stdu --help` for more info.\n",
 			err_msg
 		);
 		return 1;
@@ -34,7 +34,7 @@ Print amount of data piped to stdin.\n\
 --help | -?: print this help message\n\
 --human-readable | -h: output in a human readable format\n\
 --multiline | -m: output with line breaks\n\
---precision n | -p n | -pn: output with n significant digits\n "
+--precision n | -p n | -pn: output with n significant digits\n"
 		);
 		return 0;
 	}