When debugging, escape the buffer output.

[miniexpect.git] / miniexpect.c

diff --git a/miniexpect.c b/miniexpect.c
index 9e9cc0e..b370cfe 100644 (file)
--- a/miniexpect.c
+++ b/miniexpect.c
@@ -22,8 +22,10 @@
 #include <stdlib.h>
 #include <stdarg.h>
 #include <string.h>
+#include <ctype.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <signal.h>
 #include <poll.h>
 #include <errno.h>
 #include <termios.h>
@@ -35,10 +37,21 @@
 
 #include <pcre.h>
 
+/* RHEL 6 pcre did not define PCRE_PARTIAL_SOFT.  However PCRE_PARTIAL
+ * is a synonym so use that.
+ */
+#ifndef PCRE_PARTIAL_SOFT
+#define PCRE_PARTIAL_SOFT PCRE_PARTIAL
+#endif
+
 #include "miniexpect.h"
 
 #define DEBUG 0
 
+#if DEBUG
+static void debug_buffer (FILE *, const char *);
+#endif
+
 static mexp_h *
 create_handle (void)
 {
@@ -89,7 +102,7 @@ mexp_close (mexp_h *h)
 }
 
 mexp_h *
-mexp_spawnl (const char *file, const char *arg, ...)
+mexp_spawnlf (unsigned flags, const char *file, const char *arg, ...)
 {
   char **argv, **new_argv;
   size_t i;
@@ -107,21 +120,23 @@ mexp_spawnl (const char *file, const char *arg, ...)
     new_argv = realloc (argv, sizeof (char *) * (i+1));
     if (new_argv == NULL) {
       free (argv);
+      va_end (args);
       return NULL;
     }
     argv = new_argv;
     argv[i] = (char *) arg;
   }
 
-  h = mexp_spawnv (file, argv);
+  h = mexp_spawnvf (flags, file, argv);
   free (argv);
+  va_end (args);
   return h;
 }
 
 mexp_h *
-mexp_spawnv (const char *file, char **argv)
+mexp_spawnvf (unsigned flags, const char *file, char **argv)
 {
-  mexp_h *h;
+  mexp_h *h = NULL;
   int fd = -1;
   int err;
   char slave[1024];
@@ -151,9 +166,25 @@ mexp_spawnv (const char *file, char **argv)
     goto error;
 
   if (pid == 0) {               /* Child. */
-    struct termios terminal_settings;
     int slave_fd;
 
+    if (!(flags & MEXP_SPAWN_KEEP_SIGNALS)) {
+      struct sigaction sa;
+      int i;
+
+      /* Remove all signal handlers.  See the justification here:
+       * https://www.redhat.com/archives/libvir-list/2008-August/msg00303.html
+       * We don't mask signal handlers yet, so this isn't completely
+       * race-free, but better than not doing it at all.
+       */
+      memset (&sa, 0, sizeof sa);
+      sa.sa_handler = SIG_DFL;
+      sa.sa_flags = 0;
+      sigemptyset (&sa.sa_mask);
+      for (i = 1; i < NSIG; ++i)
+        sigaction (i, &sa, NULL);
+    }
+
     setsid ();
 
     /* Open the slave side of the pty.  We must do this in the child
@@ -163,10 +194,14 @@ mexp_spawnv (const char *file, char **argv)
     if (slave_fd == -1)
       goto error;
 
-    /* Set raw mode. */
-    tcgetattr (slave_fd, &terminal_settings);
-    cfmakeraw (&terminal_settings);
-    tcsetattr (slave_fd, TCSANOW, &terminal_settings);
+    if (!(flags & MEXP_SPAWN_COOKED_MODE)) {
+      struct termios termios;
+
+      /* Set raw mode. */
+      tcgetattr (slave_fd, &termios);
+      cfmakeraw (&termios);
+      tcsetattr (slave_fd, TCSANOW, &termios);
+    }
 
     /* Set up stdin, stdout, stderr to point to the pty. */
     dup2 (slave_fd, 0);
@@ -179,6 +214,21 @@ mexp_spawnv (const char *file, char **argv)
      */
     close (fd);
 
+    if (!(flags & MEXP_SPAWN_KEEP_FDS)) {
+      int i, max_fd;
+
+      /* Close all other file descriptors.  This ensures that we don't
+       * hold open (eg) pipes from the parent process.
+       */
+      max_fd = sysconf (_SC_OPEN_MAX);
+      if (max_fd == -1)
+        max_fd = 1024;
+      if (max_fd > 65536)
+        max_fd = 65536;      /* bound the amount of work we do here */
+      for (i = 3; i < max_fd; ++i)
+        close (i);
+    }
+
     /* Run the subprocess. */
     execvp (file, argv);
     perror (file);
@@ -197,6 +247,8 @@ mexp_spawnv (const char *file, char **argv)
     close (fd);
   if (pid > 0)
     waitpid (pid, NULL, 0);
+  if (h != NULL)
+    mexp_close (h);
   errno = err;
   return NULL;
 }
@@ -286,7 +338,9 @@ mexp_expect (mexp_h *h, const mexp_regexp *regexps, int *ovector, int ovecsize)
     h->buffer[h->len] = '\0';
 #if DEBUG
     fprintf (stderr, "DEBUG: read %zd bytes from pty\n", rs);
-    fprintf (stderr, "DEBUG: buffer content: %s\n", h->buffer);
+    fprintf (stderr, "DEBUG: buffer content: ");
+    debug_buffer (stderr, h->buffer);
+    fprintf (stderr, "\n");
 #endif
 
   try_match:
@@ -298,7 +352,7 @@ mexp_expect (mexp_h *h, const mexp_regexp *regexps, int *ovector, int ovecsize)
       assert (h->buffer != NULL);
 
       for (i = 0; regexps[i].r > 0; ++i) {
-        int options = regexps[i].options | PCRE_PARTIAL_SOFT;
+        const int options = regexps[i].options | PCRE_PARTIAL_SOFT;
 
         r = pcre_exec (regexps[i].re, regexps[i].extra,
                        h->buffer, (int)h->len, 0,
@@ -359,7 +413,9 @@ mexp_printf (mexp_h *h, const char *fs, ...)
     return -1;
 
 #if DEBUG
-  fprintf (stderr, "DEBUG: writing: %s\n", msg);
+  fprintf (stderr, "DEBUG: writing: ");
+  debug_buffer (stderr, msg);
+  fprintf (stderr, "\n");
 #endif
 
   n = len;
@@ -377,3 +433,37 @@ mexp_printf (mexp_h *h, const char *fs, ...)
   free (msg);
   return len;
 }
+
+int
+mexp_send_interrupt (mexp_h *h)
+{
+  return write (h->fd, "\003", 1);
+}
+
+#if DEBUG
+/* Print escaped buffer to fp. */
+static void
+debug_buffer (FILE *fp, const char *buf)
+{
+  while (*buf) {
+    if (isprint (*buf))
+      fputc (*buf, fp);
+    else {
+      switch (*buf) {
+      case '\0': fputs ("\\0", fp); break;
+      case '\a': fputs ("\\a", fp); break;
+      case '\b': fputs ("\\b", fp); break;
+      case '\f': fputs ("\\f", fp); break;
+      case '\n': fputs ("\\n", fp); break;
+      case '\r': fputs ("\\r", fp); break;
+      case '\t': fputs ("\\t", fp); break;
+      case '\v': fputs ("\\v", fp); break;
+      default:
+        fprintf (fp, "\\x%x", (unsigned char) *buf);
+      }
+    }
+    buf++;
+  }
+}
+#endif
+