further improvement

Signed-off-by: Mattias Andrée <maandree@member.fsf.org>

1 files changed, 83 insertions, 0 deletions

diff --git a/src/common.h b/src/common.h
index 68d465e..187723e 100644
--- a/src/common.h
+++ b/src/common.h
@@ -47,6 +47,43 @@ static const char *failed__ = NULL;
 
 
 /**
+ * A queued job.
+ */
+struct job {
+	/**
+	 * The job number.
+	 */
+	size_t no;
+
+	/**
+	 * The number of “argv” elements in `payload`.
+	 */
+	int argc;
+
+	/**
+	 * The clock in which `ts` is measured.
+	 */
+	clockid_t clk;
+
+	/**
+	 * The time when the job shall be executed.
+	 */
+	struct timespec ts;
+
+	/**
+	 * The number of bytes in `payload`.
+	 */
+	size_t n;
+
+	/**
+	 * “argv” followed by “envp”.
+	 */
+	char payload[];
+};
+
+
+
+/**
  * Defines the function `void usage(void)`
  * that prints usage information.
  * 
@@ -132,3 +169,49 @@ fail:  \
 	free(msg);  \
 	return 1;
 
+
+/**
+ * This block of code allows us to compile with DEBUG=valgrind
+ * or DEBUG=strace and have all exec:s be wrapped in
+ * valgrind --leak-check=full --show-leak-kinds=all or
+ * strace, respectively. Very useful for debugging. However,
+ * children do not inherit strace, so between forking and
+ * exec:ing we do not have strace.
+ */
+#if 1 && defined(DEBUG)
+# if ((DEBUG == 2) || (DEBUG == 3))
+#  ifdef __GNUC__
+#   pragma GCC diagnostic push
+#   pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
+__attribute__((__used__))
+#  endif
+#  if DEBUG == 2
+#   define DEBUGPROG  "strace"
+#  else
+#   define DEBUGPROG  "valgrind"
+#  endif
+#  define execl(path, _, ...) (execl)("/usr/bin/" DEBUGPROG, "/usr/bin/" DEBUGPROG, path, __VA_ARGS__)
+#  define execve(...) execve_(__VA_ARGS__)
+static int
+execve_(const char *path, char *const argv[], char *const envp[])
+{
+	size_t n = 0;
+	char **new_argv = NULL;
+	int x = (DEBUG - 2) * 2, saved_errno;
+	while (argv[n++]);
+	t (!(new_argv = malloc((n + 1 + (size_t)x) * sizeof(char *))));
+	new_argv[x] = "--show-leak-kinds=all";
+	new_argv[1] = "--leak-check=full";
+	new_argv[0] = "/usr/bin/" DEBUGPROG;
+	new_argv[1 + x] = path;
+	memcpy(new_argv + 2 + x, argv + 1, (n - 1) * sizeof(char *));
+	(execve)(*new_argv, new_argv, envp);
+fail:
+	return saved_errno = errno, free(new_argv), errno = saved_errno, -1;
+}
+#  ifdef __GNUC__
+#   pragma GCC diagnostic pop
+#  endif
+# endif
+#endif
+