Improve management of zlib dependency

Summary:
  - Add zlib functions to extension functions.
  - Provide a better error if the extension is actually missing.

Test Plan: Eyeballed it.

Reviewers: vrana, btrahan

Reviewed By: btrahan

CC: Korvin, aran

Differential Revision: https://secure.phabricator.com/D3321

scripts/lib/PhutilLibraryMapBuilder.php

@@ -37,7 +37,7 @@ final class PhutilLibraryMapBuilder {
   const LIBRARY_MAP_VERSION       = 2;
 
   const SYMBOL_CACHE_VERSION_KEY  = '__symbol_cache_version__';
-  const SYMBOL_CACHE_VERSION      = 7;
+  const SYMBOL_CACHE_VERSION      = 8;
 
 
 /* -(  Mapping libphutil Libraries  )---------------------------------------- */

scripts/php_extension_functions.txt

@@ -51,6 +51,26 @@ curl_share_init
 curl_share_setopt
 curl_unescape
 curl_version
+gzrewind
+gzclose
+gzeof
+gzgetc
+gzgets
+gzgetss
+gzread
+gzopen
+gzpassthru
+gzseek
+gztell
+gzwrite
+gzputs
+gzfile
+gzcompress
+gzuncompress
+gzdeflate
+gzinflate
+gzencode
+gzdecode
 image2wbmp
 image_type_to_extension
 image_type_to_mime_type

src/parser/ArcanistBundle.php

@@ -655,6 +655,13 @@ final class ArcanistBundle {
   }
 
   private function emitBinaryDiffBody($data) {
+    if (!function_exists('gzcompress')) {
+      throw new Exception(
+        "This patch has binary data. The PHP zlib extension is required to ".
+        "apply patches with binary data to git. Install the PHP zlib ".
+        "extension to continue.");
+    }
+
     // See emit_binary_diff_body() in diff.c for git's implementation.
 
     $buf = '';