Tests for the shell

shell/shell-test.c

+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <fcntl.h>
+
+#include <sys/types.h>
+#include <sys/wait.h>
+
+int create_shell_process(char **argv, int *in, int *out) {
+  int in_pipe[2];
+  int out_pipe[2];
+
+  if (pipe(in_pipe) < 0)
+    return -1;
+
+  if (pipe(out_pipe) < 0)
+    return -1;
+
+  int pid = fork();
+  if (pid == 0) {
+    // we're in the child
+
+    // close the reading end of the out pipe
+    close(out_pipe[0]);
+    // close the writing end of the in pipe
+    close(in_pipe[1]);
+    // redirect stdout to the writing end of the out pipe
+    dup2(out_pipe[1], STDOUT_FILENO);
+    // redirect stdin to the reading end of the in pipe
+    dup2(in_pipe[0], STDIN_FILENO);
+    // now run the executable
+    char *args[3] = {argv[0], argv[1], NULL};
+    execv(argv[0], args);
+  }
+
+  if (pid < 0)
+    return -1;
+
+  // we're in the parent
+  close(out_pipe[1]);
+  close(in_pipe[0]);
+
+
+  // configure the reads to be non-blocking
+  int flags = fcntl(out_pipe[0], F_GETFL);
+  fcntl(out_pipe[0], F_SETFL, flags | O_NONBLOCK);
+
+  *in = in_pipe[1];
+  *out = out_pipe[0];
+
+  return pid;
+}
+
+int send_command(const char *cmd, char *result, size_t result_size, int sleep_sec, int in, int out) {
+  memset(result, 0, result_size);
+  int t0 = time(NULL);
+  if (write(in, cmd, strlen(cmd)) < 0) {
+    return -1;
+  }
+  if (sleep_sec) {
+    // wait for the result
+    sleep(sleep_sec);
+  }
+  read(out, result, result_size - 1);
+  int t1 = time(NULL);
+  return t1 - t0;
+}
+
+
+
+#define TEST_SLEEP(cmd, expected, sleep) do {					\
+  printf("================================================================================\n");\
+  printf(" RUN: %s", cmd); \
+  int t = send_command(cmd, result_buf, sizeof(result_buf), sleep, in, out); \
+  if (t < 0) { \
+    printf("Error while sending commands to the shell."); \
+  } \
+  if (strcmp(result_buf, expected)) {\
+    ++n_fail;\
+    printf("[FAIL] Expected '%s', but got '%s'.\n", expected, result_buf); \
+  } else {\
+    ++n_pass;\
+    printf("[PASS]\n");\
+  }\
+  } while(0);
+
+#define TEST(cmd, expected) \
+  TEST_SLEEP(cmd, expected, 1)
+
+int main(int argc, char **argv) {
+  // create a temporary directory where to run the tests
+  char tmp_dir_template[] = "test-dir-XXXXXX";
+  char *tmp_dir = mkdtemp(tmp_dir_template);
+  if (!chdir(tmp_dir)) {
+    printf("Using test directory %s\n", tmp_dir);
+  }
+  char cwd[1000];
+  getcwd(cwd, sizeof(cwd));
+
+  // start the shell process
+  int in, out;
+  int shell_pid = create_shell_process(&argv[1], &in, &out);
+  if (shell_pid < 0) {
+    printf("Error launching the shell");
+    exit(1);
+  }
+
+  // run the tests here
+  char result_buf[1000];
+  int n_pass = 0;
+  int n_fail = 0;
+
+
+  TEST("pwd\n", cwd);
+  TEST("/bin/pwd\n", cwd);
+  TEST("touch file1.txt\n", "");
+  TEST("ls\n", "file1.txt");
+  TEST_SLEEP("sleep 5; echo 'hello'\n", "hello", 6);
+  TEST("sleep 5 & echo 'hello'\n", "hello");
+  TEST("echo line1 > file1.txt\n", "");
+  TEST("cat < file1.txt\n", "line1");
+  TEST("cat file1.txt | wc -l\n", "1");
+  TEST("cat file1.txt | cat | cat | cat | cat | wc -l\n", "1");
+
+  close(in);
+
+  int wstatus;
+  waitpid(shell_pid, &wstatus, 0);
+}