Bug 1468544 - Replace mar_hash_name with CityHash algorithm. r=rstrong

Make CityHash64, CityHash64WithSeed, and CityHash64WithSeeds usable from C code
Remove unnecessary includes from mar_read.c as well
Add DisableStlWrapping to mar tool's moz.build to fix linkage break when
building in Windows with MSVC

Differential Revision: https://phabricator.services.mozilla.com/D10774

modules/libmar/src/mar_read.c

@@ -8,15 +8,10 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include <string.h>
+#include "city.h"
 #include "mar_private.h"
 #include "mar.h"
 
-#ifdef XP_WIN
-#include <winsock2.h>
-#else
-#include <netinet/in.h>
-#endif
-
 /* This block must be at most 104 bytes.
    MAR channel name < 64 bytes, and product version < 32 bytes + 3 NULL
    terminator bytes. We only check for 96 though because we remove 8
@@ -24,15 +19,8 @@
    sizeof(additionalBlockSize) and sizeof(additionalBlockID) */
 #define MAXADDITIONALBLOCKSIZE 96
 
-/* this is the same hash algorithm used by nsZipArchive.cpp */
 static uint32_t mar_hash_name(const char *name) {
-  uint32_t val = 0;
-  unsigned char* c;
-
-  for (c = (unsigned char *) name; *c; ++c)
-    val = val*37 + *c;
-
-  return val % TABLESIZE;
+  return CityHash64(name, strlen(name)) % TABLESIZE;
 }
 
 static int mar_insert_item(MarFile *mar, const char *name, int namelen,

modules/libmar/src/moz.build

@@ -24,6 +24,10 @@ UNIFIED_SOURCES += [
     'mar_read.c',
 ]
 
+LOCAL_INCLUDES += [
+    '../../../other-licenses/nsis/Contrib/CityHash/cityhash',
+]
+
 FORCE_STATIC_LIB = True
 
 if CONFIG['OS_ARCH'] == 'WINNT':

modules/libmar/tool/moz.build

@@ -5,6 +5,7 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 HOST_SOURCES += [
+    '/other-licenses/nsis/Contrib/CityHash/cityhash/city.cpp',
     'mar.c',
 ]
 
@@ -58,4 +59,6 @@ if CONFIG['HOST_OS_ARCH'] == 'WINNT':
         'ws2_32',
     ]
 
+DisableStlWrapping()
+
 HOST_DEFINES['NO_SIGN_VERIFY'] = True

other-licenses/nsis/Contrib/CityHash/cityhash/city.h

@@ -50,6 +50,7 @@ typedef uint8_t uint8;
 typedef uint32_t uint32;
 typedef uint64_t uint64;
 
+#ifdef __cplusplus
 // The standard <utility> header doesn't compile, apparently it conflicts
 // with... some Mozilla something or other. But all that's used from it
 // is std::pair, so we can just replace that with mozilla::Pair.
@@ -65,6 +66,8 @@ inline uint64 Uint128Low64(const uint128& x) { return x.first(); }
 inline uint64 Uint128High64(const uint128& x) { return x.second(); }
 #endif
 
+extern "C" {
+#endif
 
 // Hash function for a byte array.
 uint64 CityHash64(const char *buf, size_t len);
@@ -78,6 +81,8 @@ uint64 CityHash64WithSeed(const char *buf, size_t len, uint64 seed);
 uint64 CityHash64WithSeeds(const char *buf, size_t len,
                            uint64 seed0, uint64 seed1);
 
+#ifdef __cplusplus
+}
 // Hash function for a byte array.
 uint128 CityHash128(const char *s, size_t len);
 
@@ -97,5 +102,6 @@ inline uint64 Hash128to64(const uint128& x) {
   b *= kMul;
   return b;
 }
+#endif
 
 #endif  // CITY_HASH_H_