uint64_t read_counter_from_proc()

in src/oscounter.c [166:225]

• 44 lines of code
• 10 McCabe index (conditional complexity)

uint64_t read_counter_from_proc(char *file_name, char *section, char *key)
{
	char *log;
	FILE *stream;
	char *line = NULL, *pch = NULL;
	size_t len = 0;
	ssize_t read;
	int key_found = 0;
	uint64_t ret = 0;

	stream = fopen(file_name, "r");
	if (!stream) {
		ASPRINTF(&log, "failed to open file: %s. errno = %d", file_name, errno);
		PRINT_ERR_FREE(log);
		return 0;
	}

	/*
	 * example:
	 *
	 * Tcp: ... OutSegs RetransSegs InErrs OutRsts InCsumErrors
	 * Tcp: ... 8584582 27 0 5 0
	 *
	 * the first line contains the key;
	 * if a key is found, then,
	 * read the corresponding cell as value from next line
	 */
	while ((read = getline(&line, &len, stream)) != -1) {
		/* key is found, then read the value here */
		if (key_found > 0) {
			pch = line;
			while ((pch = strtok(pch, " "))) {
				key_found--;
				if (key_found == 0) {
					ret = strtoull(pch, NULL, 10);
					goto found;
				}
				pch = NULL;
			}
		}
		/* try to locate the key */
		if (strcmp(section, line) < 0) {
			if (strstr(line, key) != NULL) {
				pch = line;
				while ((pch = strtok(pch, " "))) {
					key_found++;
					if (strcmp(pch, key) == 0)
						break;
					pch = NULL;
				}
			}
		}
	}

found:
	free(line);
	fclose(stream);

	return ret;
}