Refactored configuration parsing to a separate file and added unit tests to it

1 files changed, 8 insertions, 144 deletions

diff --git a/stdu.c b/stdu.c
index 43038a8..f7f5511 100644
--- a/stdu.c
+++ b/stdu.c
@@ -6,144 +6,11 @@
 #include <stdbool.h>
 
 #include "intmath.h"
+#include "config-parser.h"
 
 int tests_run = 0;
 int tests_failed = 0;
 
-struct Config {
-	int precision;
-	bool human_readable;
-};
-typedef struct Config Config;
-struct Result {
-	bool success;
-	void* result;
-};
-typedef struct Result Result;
-
-Result parse_config(int argc, char* argv[]) {
-	Result res;
-	res.success = false;
-	Config tmp;
-	tmp.precision = 0;
-	tmp.human_readable = false;
-
-	size_t i = 1;
-	char* argument;
-	char* precision = NULL;
-	while (i < argc) {
-		argument = argv[i];
-		int comp1 = strcmp(argument, "--precision") == 0;
-		if (
-			comp1 || strncmp(argument, "-p", 2) == 0
-		) {
-			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;
-			}
-			i++;
-			if (strlen(argument) != 2 && !comp1) {
-				precision = argument + 2;
-				continue;
-			}
-			if (i == argc) {
-				char* error_msg = malloc(57);
-				snprintf(
-					error_msg,
-					57,
-					"`%s` should be followed by an integer argument",
-					argument
-				);
-				res.result = error_msg;
-				return res;
-			}
-			precision = argv[i];
-		} else if (
-			strcmp(argument, "--human-readable") == 0
-			|| strcmp(argument, "-h") == 0
-		) {
-			if (tmp.human_readable != false) {
-				char* error_msg = malloc(52);
-				snprintf(
-					error_msg,
-					52,
-					"human readability can't be specified multiple times"
-				);
-				res.result = error_msg;
-				return res;
-			}
-			tmp.human_readable = true;
-		} 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;
-		}
-
-		i++;
-	}
-
-	if (precision != NULL) {
-		char* endptr;
-		errno = 0;
-		tmp.precision = (int) strtol(precision, &endptr, 10);
-		if (errno != 0) {
-			char* error_msg = malloc(64);
-			char* errno_str = strerror(errno);
-			snprintf(
-				error_msg,
-				64,
-				"invalid precision: %s",
-				errno_str
-			);
-			free(errno_str);
-			res.result = error_msg;
-			return res;
-		}
-		if (*endptr != '\0') {
-			char* error_msg = malloc(53);
-			snprintf(
-				error_msg,
-				53,
-				"the precision may not contain non-numeric characters",
-				precision
-			);
-			res.result = error_msg;
-			return res;
-		}
-		if (tmp.precision <= 0) {
-			char* error_msg = malloc(50);
-			snprintf(
-				error_msg,
-				50,
-				"the precision can't be less than or equal to zero"
-			);
-			res.result = error_msg;
-			return res;
-		}
-	}
-
-	Config* conf = malloc(sizeof(int) + sizeof(bool));
-	conf->precision = tmp.precision;
-	conf->human_readable = tmp.human_readable;
-
-	res.success = true;
-	res.result = conf;
-	return res;
-}
-
 int main (int argc, char* argv[]) {
 	Result res = parse_config(argc, argv);
 	if (res.success == false) {
@@ -157,14 +24,11 @@ int main (int argc, char* argv[]) {
 	}
 
 	Config* conf = (Config*) res.result;
-	int precision = conf->precision;
-	bool human_readable = conf->human_readable;
-	printf("precision: %d\n", precision);
-	if (human_readable) printf("human readable\n");
+	if (conf->human_readable) printf("human readable\n");
 
 	unsigned int base = 10;
-	if (human_readable && precision == 0) {
-		precision = 1;
+	if (conf->human_readable && conf->precision == 0) {
+		conf->precision = 1;
 		base = 1024;
 	}
 
@@ -172,10 +36,10 @@ int main (int argc, char* argv[]) {
 	size_t bufsize = 1;
 	unsigned int bytes_read = 0;
 	size_t new_read_bytes = 0;
-	if (precision != 0) {
+	if (conf->precision != 0) {
 		blocksize = exp_notated_to_int(int_ceiled_exponent_notation_base(
 			bytes_read + 1,
-			precision,
+			conf->precision,
 			base))
 			- bytes_read;
 		bufsize = 1024;
@@ -214,10 +78,10 @@ int main (int argc, char* argv[]) {
 		/* resizing buffer and blocksize to read as much as possible
 		 * at once
 		 */
-		if (precision == 0) continue;
+		if (conf->precision == 0) continue;
 		blocksize = exp_notated_to_int(int_ceiled_exponent_notation_base(
 			bytes_read + 1,
-			precision,
+			conf->precision,
 			base))
 			- bytes_read;
 		if (blocksize > bufsize) {