gists/c-programming/pure_getline.c

/*
 * pure_getline.c
 *
 * Author: Intel A80486DX2-66
 * License: Creative Commons Zero 1.0 Universal
*/

#include "pure_getline.h"

bool pure_getline(char** output) {
	/*
	 * return value:
	 * 	true: no errors
	 * 	false: an error occurred, see errno
	 */

	char* line = NULL;
	size_t len = 0;
	int character;
	bool past_first_time = false;

	while ((character = fgetc(stdin)) != EOF) {
		if (past_first_time && len == 0) { // check for integer overflow
			errno = ERANGE;
			*output = NULL;
			return false;
		}

		char* new_line = realloc(line, (len + 1) * sizeof(char));

		if (new_line == NULL) {
			*output = line;
			return false;
		}

		line = new_line;

		if (character == '\n') {
			line[len] = '\0';
			break;
		}
		line[len++] = character;
		past_first_time = true;
	}

	*output = line;
	return true;
}