[gtk-osx] Patch CFStringGetCStringPtr blunder in gio.

[John Ralls <jralls src gnome org>]

commit f333bb9b866bc0cbfaff0eb9d665ddac0f2f7877
Author: John Ralls <jralls ceridwen us>
Date:   Fri Oct 13 14:12:48 2017 -0700

    Patch CFStringGetCStringPtr blunder in gio.

 modulesets-stable/gtk-osx.modules                  |    2 +
 ...ack-to-CFStringGetCSTring-if-CFStringGetC.patch |  116 ++++++++++++++++++++
 2 files changed, 118 insertions(+), 0 deletions(-)
---
diff --git a/modulesets-stable/gtk-osx.modules b/modulesets-stable/gtk-osx.modules
index 800b964..fa52834 100644
--- a/modulesets-stable/gtk-osx.modules
+++ b/modulesets-stable/gtk-osx.modules
@@ -80,6 +80,8 @@
     <branch module="glib/2.52/glib-2.52.2.tar.xz"  version="2.52.2"
             hash="sha256:f00e5d9e2a2948b1da25fcba734a6b7a40f556de8bc9f528a53f6569969ac5d0">
       <patch file="https://git.gnome.org/browse/gtk-osx/plain/patches/glib-gint64-long-long.patch"; 
strip="1"/>
+      <!-- Fix should be in glib-2.54.2 -->
+      <patch 
file='https://git.gnome.org/browse/gtk-osx/plain/patches/glib-2.52-Fallback-to-CFStringGetCSTring-if-CFStringGetC.patch";
 strip="1"/>
     </branch>
     <dependencies>
         <dep package="libffi"/>
diff --git a/patches/glib-2.52-Fallback-to-CFStringGetCSTring-if-CFStringGetC.patch 
b/patches/glib-2.52-Fallback-to-CFStringGetCSTring-if-CFStringGetC.patch
new file mode 100644
index 0000000..5155813
--- /dev/null
+++ b/patches/glib-2.52-Fallback-to-CFStringGetCSTring-if-CFStringGetC.patch
@@ -0,0 +1,116 @@
+From d5a9ce69c46a907af8ed3af0020d2a409faa3751 Mon Sep 17 00:00:00 2001
+From: John Ralls <jralls ceridwen us>
+Date: Fri, 13 Oct 2017 13:45:01 -0700
+Subject: [PATCH] [MacOS] Fallback to CFStringGetCSTring if
+ CFStringGetCStringPtr fails.
+
+---
+ gio/gosxappinfo.c     | 34 ++++++++++++++++++++++++++++++++--
+ gio/gosxcontenttype.c | 34 ++++++++++++++++++++++++++++++++--
+ 2 files changed, 64 insertions(+), 4 deletions(-)
+
+diff --git a/gio/gosxappinfo.c b/gio/gosxappinfo.c
+index b24b6ff..7c2b402 100644
+--- a/gio/gosxappinfo.c
++++ b/gio/gosxappinfo.c
+@@ -175,14 +175,44 @@ static gchar *
+ create_cstr_from_cfstring (CFStringRef str)
+ {
+   const gchar *cstr;
++  CFIndex length = CFStringGetLength (str);
++  char *buffer = NULL;
+ 
+   if (str == NULL)
+     return NULL;
+ 
+   cstr = CFStringGetCStringPtr (str, kCFStringEncodingUTF8);
++  /* CFStringGetCStringPtr returns "NULL if the internal storage of
++   * theString does not allow [a pointer] to be returned efficiently".
++   * (Apple's docs don't say what that means). In that case we must
++   * use CFStringGetCString as a fallback.
++   */
++  if (cstr != NULL)
++    {
++        CFRelease (str);
++        return g_strdup (cstr);
++    }
++  
++  buffer = g_malloc0 (length + 1);
++  /* Start off with a buffer size sufficient for the most likely case
++   * that the CFString is ASCII so the UTF8 representation will be 1
++   * byte per code point. Keep trying up to 4 bytes per code point,
++   * the max allowed by RFC3629.
++   */
++  for (int i = 1; i <= 4; ++i)
++    {
++      if (CFStringGetCString (str, buffer, length, kCFStringEncodingUTF8))
++      {
++        CFRelease (str);
++        return buffer;
++      }
++      length += length;
++      buffer = g_realloc (buffer, length + 1);
++    }
++  
++  g_free (buffer);
+   CFRelease (str);
+-
+-  return g_strdup (cstr);
++  return NULL;
+ }
+ 
+ static char *
+diff --git a/gio/gosxcontenttype.c b/gio/gosxcontenttype.c
+index 485f5bf..c046d9e 100644
+--- a/gio/gosxcontenttype.c
++++ b/gio/gosxcontenttype.c
+@@ -53,14 +53,44 @@ static gchar *
+ create_cstr_from_cfstring (CFStringRef str)
+ {
+   const gchar *cstr;
++  CFIndex length = CFStringGetLength (str);
++  char *buffer = NULL;
+ 
+   if (str == NULL)
+     return NULL;
+ 
+   cstr = CFStringGetCStringPtr (str, kCFStringEncodingUTF8);
++  /* CFStringGetCStringPtr returns "NULL if the internal storage of
++   * theString does not allow [a pointer] to be returned efficiently".
++   * (Apple's docs don't say what that means). In that case we must
++   * use CFStringGetCString as a fallback.
++   */
++  if (cstr != NULL)
++    {
++        CFRelease (str);
++        return g_strdup (cstr);
++    }
++  
++  buffer = g_malloc0 (length + 1);
++  /* Start off with a buffer size sufficient for the most likely case
++   * that the CFString is ASCII so the UTF8 representation will be 1
++   * byte per code point. Keep trying up to 4 bytes per code point,
++   * the max allowed by RFC3629.
++   */
++  for (int i = 1; i <= 4; ++i)
++    {
++      if (CFStringGetCString (str, buffer, length, kCFStringEncodingUTF8))
++        {
++          CFRelease (str);
++          return buffer;
++        }
++      length += length;
++      buffer = g_realloc (buffer, length + 1);
++    }
++  
++  g_free (buffer);
+   CFRelease (str);
+-
+-  return g_strdup (cstr);
++  return NULL;
+ }
+ 
+ /*< internal >
+-- 
+2.2.2
+