build: Add strchrnul implementation to fix compilation on macOS

https://bugzilla.gnome.org/show_bug.cgi?id=788476
(cherry picked from commit a4362e9)

configure.ac

@@ -294,6 +294,9 @@ AC_CHECK_FUNCS([cfmakeraw fork setsid setpgid getpgid tcgetattr tcsetattr])
 AC_CHECK_FUNCS([pread pwrite])
 AC_CHECK_FUNCS([explicit_bzero])
 
+# Misc string routines.
+AC_CHECK_FUNCS([strchrnul])
+
 # for vtespawn
 AC_CHECK_HEADERS([sys/resource.h])
 AC_CHECK_FUNCS([fdwalk])

src/vteseq.cc

@@ -31,6 +31,7 @@
 #include <vte/vte.h>
 #include "vteinternal.hh"
 #include "vtegtk.hh"
+#include "vteutils.h"  /* for strchrnul on non-GNU systems */
 #include "caps.h"
 #include "debug.h"
 

src/vtespawn.cc

@@ -40,6 +40,7 @@
 #include <glib-unix.h>
 
 #include "vtespawn.hh"
+#include "vteutils.h"  /* for strchrnul on non-GNU systems */
 #include "reaper.hh"
 
 #define VTE_SPAWN_ERROR_TIMED_OUT (G_SPAWN_ERROR_FAILED + 1000)
@@ -1002,16 +1003,6 @@ script_execute (const gchar *file,
   }
 }
 
-static gchar*
-my_strchrnul (const gchar *str, gchar c)
-{
-  gchar *p = (gchar*) str;
-  while (*p && (*p != c))
-    ++p;
-
-  return p;
-}
-
 static gint
 g_execute (const gchar *file,
            gchar      **argv,
@@ -1082,7 +1073,7 @@ g_execute (const gchar *file,
 	  char *startp;
 
 	  path = p;
-	  p = my_strchrnul (path, ':');
+	  p = strchrnul (path, ':');
 
 	  if (p == path)
 	    /* Two adjacent colons, or a colon at the beginning or the end

src/vteutils.cc

@@ -96,3 +96,16 @@ _vte_mkstemp (void)
 
         return fd;
 }
+
+#ifndef HAVE_STRCHRNUL
+/* Copied from glib */
+char *
+strchrnul (const char *s, int c)
+{
+        char *p = (char *) s;
+        while (*p && (*p != c))
+                ++p;
+
+        return p;
+}
+#endif /* !HAVE_STRCHRNUL */

src/vteutils.h

@@ -24,6 +24,9 @@
 G_BEGIN_DECLS
 
 int _vte_mkstemp (void);
+#ifndef HAVE_STRCHRNUL
+char *strchrnul (const char *s, int c);
+#endif
 
 G_END_DECLS