add rudimentary unit tests, and logging timestamps

Signed-off-by: Aidan Hahn <aidan@aidanis.online>

tests/log_test.c

@@ -0,0 +1,82 @@
+#include "../alog.h"
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <stdio.h>
+#include <string.h>
+
+int out_fd[2];
+int err_fd[2];
+
+const char *out_message = "standard message";
+const char *err_message = "error message";
+
+int main() {
+  // make RPC pipe
+  pipe(out_fd);
+  pipe(err_fd);
+
+  // remove stdout and stderr
+  _init_alog();
+  alog_remove_target(1);
+  alog_remove_target(2);
+
+  pid_t childpid;
+  if ((childpid = fork()) == -1) {
+    perror("fork fail");
+    return 1;
+  }
+
+  // child process
+  if (childpid == 0) {
+    close(out_fd[0]);
+    close(err_fd[0]);
+
+    // add alog targets in this pipe
+    alog_add_target(out_fd[1], ALOG_OUT);
+    alog_add_target(err_fd[1], ALOG_ERR);
+
+    // write to the things
+    alog(ERROR, err_message);
+    alog(PRINT, out_message);
+
+    exit(0);
+  // parent process
+  } else {
+    // we can do checks from here
+    char out_read_buffer[128] = {0};
+    char err_read_buffer[128] = {0};
+
+    usleep(10);
+
+    read(err_fd[0], err_read_buffer, 128);
+    // cant check read len because of timestamp
+    if (!strstr(err_read_buffer, err_message)) {
+      printf("err log should contain '%s'.\ninstead reads '%s'\n",
+             err_message, err_read_buffer);
+      return 1;
+    }
+
+    int num_out = read(out_fd[0], out_read_buffer, 128);
+    if (num_out != (int) (strlen(out_message) + strlen(err_read_buffer))) {
+      printf("Read %i bytes from out log when %lu were written!\n",
+             num_out, strlen(out_message) + strlen(err_read_buffer) + 1);
+      return 1;
+    }
+    if (strncmp(out_read_buffer, err_read_buffer, strlen(err_read_buffer))) {
+      printf("out log first message should read '%s'.\ninstead reads '%s'\n",
+             err_read_buffer, out_read_buffer);
+    }
+    if (strcmp(&out_read_buffer[strlen(err_read_buffer)], out_message)) {
+      printf("out log second message should read '%s'.\ninstead reads '%s'\n",
+             out_message, &out_read_buffer[strlen(err_read_buffer)]);
+      return 1;
+    }
+
+
+    printf("out and err log printing are successfull.\n");
+  }
+
+  deinit_alog();
+  return 0;
+}