1 files changed, 51 insertions, 58 deletions

diff --git a/applypatch/imgdiff.cpp b/applypatch/imgdiff.cpp
index 7d6ebab6e..2f0e1651c 100644
--- a/applypatch/imgdiff.cpp
+++ b/applypatch/imgdiff.cpp
@@ -121,19 +121,23 @@
  * information that is stored on the system partition.
  */
 
+#include "applypatch/imgdiff.h"
+
 #include <errno.h>
-#include <inttypes.h>
+#include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
-#include <unistd.h>
 #include <sys/types.h>
+#include <unistd.h>
+
+#include <android-base/file.h>
+#include <android-base/unique_fd.h>
 
 #include <bsdiff.h>
+#include <zlib.h>
 
-#include "zlib.h"
-#include "imgdiff.h"
 #include "utils.h"
 
 typedef struct {
@@ -375,8 +379,7 @@ unsigned char* ReadZip(const char* filename,
  * return value when done with all the chunks.  Returns NULL on
  * failure.
  */
-unsigned char* ReadImage(const char* filename,
-                         int* num_chunks, ImageChunk** chunks) {
+unsigned char* ReadImage(const char* filename, int* num_chunks, ImageChunk** chunks) {
   struct stat st;
   if (stat(filename, &st) != 0) {
     printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
@@ -384,19 +387,12 @@ unsigned char* ReadImage(const char* filename,
   }
 
   size_t sz = static_cast<size_t>(st.st_size);
-  unsigned char* img = static_cast<unsigned char*>(malloc(sz + 4));
-  FILE* f = fopen(filename, "rb");
-  if (fread(img, 1, sz, f) != sz) {
+  unsigned char* img = static_cast<unsigned char*>(malloc(sz));
+  android::base::unique_fd fd(open(filename, O_RDONLY));
+  if (!android::base::ReadFully(fd, img, sz)) {
     printf("failed to read \"%s\" %s\n", filename, strerror(errno));
-    fclose(f);
-    return NULL;
+    return nullptr;
   }
-  fclose(f);
-
-  // append 4 zero bytes to the data so we can always search for the
-  // four-byte string 1f8b0800 starting at any point in the actual
-  // file data, without special-casing the end of the data.
-  memset(img+sz, 0, 4);
 
   size_t pos = 0;
 
@@ -404,7 +400,7 @@ unsigned char* ReadImage(const char* filename,
   *chunks = NULL;
 
   while (pos < sz) {
-    unsigned char* p = img+pos;
+    unsigned char* p = img + pos;
 
     if (sz - pos >= 4 &&
         p[0] == 0x1f && p[1] == 0x8b &&
@@ -414,8 +410,7 @@ unsigned char* ReadImage(const char* filename,
       size_t chunk_offset = pos;
 
       *num_chunks += 3;
-      *chunks = static_cast<ImageChunk*>(realloc(*chunks,
-          *num_chunks * sizeof(ImageChunk)));
+      *chunks = static_cast<ImageChunk*>(realloc(*chunks, *num_chunks * sizeof(ImageChunk)));
       ImageChunk* curr = *chunks + (*num_chunks-3);
 
       // create a normal chunk for the header.
@@ -503,8 +498,7 @@ unsigned char* ReadImage(const char* filename,
       // the decompression.
       size_t footer_size = Read4(p-4);
       if (footer_size != curr[-2].len) {
-        printf("Error: footer size %zu != decompressed size %zu\n",
-            footer_size, curr[-2].len);
+        printf("Error: footer size %zu != decompressed size %zu\n", footer_size, curr[-2].len);
         free(img);
         return NULL;
       }
@@ -522,10 +516,8 @@ unsigned char* ReadImage(const char* filename,
       curr->data = p;
 
       for (curr->len = 0; curr->len < (sz - pos); ++curr->len) {
-        if (p[curr->len] == 0x1f &&
-            p[curr->len+1] == 0x8b &&
-            p[curr->len+2] == 0x08 &&
-            p[curr->len+3] == 0x00) {
+        if (sz - pos >= 4 && p[curr->len] == 0x1f && p[curr->len + 1] == 0x8b &&
+            p[curr->len + 2] == 0x08 && p[curr->len + 3] == 0x00) {
           break;
         }
       }
@@ -624,12 +616,12 @@ int ReconstructDeflateChunk(ImageChunk* chunk) {
 }
 
 /*
- * Given source and target chunks, compute a bsdiff patch between them
- * by running bsdiff in a subprocess.  Return the patch data, placing
- * its length in *size.  Return NULL on failure.  We expect the bsdiff
- * program to be in the path.
+ * Given source and target chunks, compute a bsdiff patch between them.
+ * Return the patch data, placing its length in *size. Return NULL on failure.
+ * |bsdiff_cache| can be used to cache the suffix array if the same |src| chunk
+ * is used repeatedly, pass nullptr if not needed.
  */
-unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
+unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size, saidx_t** bsdiff_cache) {
   if (tgt->type == CHUNK_NORMAL) {
     if (tgt->len <= 160) {
       tgt->type = CHUNK_RAW;
@@ -638,7 +630,11 @@ unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
     }
   }
 
+#if defined(__ANDROID__)
+  char ptemp[] = "/data/local/tmp/imgdiff-patch-XXXXXX";
+#else
   char ptemp[] = "/tmp/imgdiff-patch-XXXXXX";
+#endif
   int fd = mkstemp(ptemp);
 
   if (fd == -1) {
@@ -649,7 +645,7 @@ unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
   close(fd); // temporary file is created and we don't need its file
              // descriptor
 
-  int r = bsdiff::bsdiff(src->data, src->len, tgt->data, tgt->len, ptemp);
+  int r = bsdiff::bsdiff(src->data, src->len, tgt->data, tgt->len, ptemp, bsdiff_cache);
   if (r != 0) {
     printf("bsdiff() failed: %d\n", r);
     return NULL;
@@ -794,10 +790,8 @@ void MergeAdjacentNormalChunks(ImageChunk* chunks, int* num_chunks) {
   *num_chunks = out;
 }
 
-ImageChunk* FindChunkByName(const char* name,
-                            ImageChunk* chunks, int num_chunks) {
-  int i;
-  for (i = 0; i < num_chunks; ++i) {
+ImageChunk* FindChunkByName(const char* name, ImageChunk* chunks, int num_chunks) {
+  for (int i = 0; i < num_chunks; ++i) {
     if (chunks[i].type == CHUNK_DEFLATE && chunks[i].filename &&
         strcmp(name, chunks[i].filename) == 0) {
       return chunks+i;
@@ -813,11 +807,11 @@ void DumpChunks(ImageChunk* chunks, int num_chunks) {
     }
 }
 
-int main(int argc, char** argv) {
-  int zip_mode = 0;
+int imgdiff(int argc, const char** argv) {
+  bool zip_mode = false;
 
   if (argc >= 2 && strcmp(argv[1], "-z") == 0) {
-    zip_mode = 1;
+    zip_mode = true;
     --argc;
     ++argv;
   }
@@ -881,12 +875,10 @@ int main(int argc, char** argv) {
     // Verify that the source and target images have the same chunk
     // structure (ie, the same sequence of deflate and normal chunks).
 
-    if (!zip_mode) {
-        // Merge the gzip header and footer in with any adjacent
-        // normal chunks.
-        MergeAdjacentNormalChunks(tgt_chunks, &num_tgt_chunks);
-        MergeAdjacentNormalChunks(src_chunks, &num_src_chunks);
-    }
+    // Merge the gzip header and footer in with any adjacent
+    // normal chunks.
+    MergeAdjacentNormalChunks(tgt_chunks, &num_tgt_chunks);
+    MergeAdjacentNormalChunks(src_chunks, &num_src_chunks);
 
     if (num_src_chunks != num_tgt_chunks) {
       printf("source and target don't have same number of chunks!\n");
@@ -898,8 +890,7 @@ int main(int argc, char** argv) {
     }
     for (i = 0; i < num_src_chunks; ++i) {
       if (src_chunks[i].type != tgt_chunks[i].type) {
-        printf("source and target don't have same chunk "
-                "structure! (chunk %d)\n", i);
+        printf("source and target don't have same chunk structure! (chunk %d)\n", i);
         printf("source chunks:\n");
         DumpChunks(src_chunks, num_src_chunks);
         printf("target chunks:\n");
@@ -980,30 +971,31 @@ int main(int argc, char** argv) {
   unsigned char** patch_data = static_cast<unsigned char**>(malloc(
       num_tgt_chunks * sizeof(unsigned char*)));
   size_t* patch_size = static_cast<size_t*>(malloc(num_tgt_chunks * sizeof(size_t)));
+  saidx_t* bsdiff_cache = nullptr;
   for (i = 0; i < num_tgt_chunks; ++i) {
     if (zip_mode) {
       ImageChunk* src;
       if (tgt_chunks[i].type == CHUNK_DEFLATE &&
-          (src = FindChunkByName(tgt_chunks[i].filename, src_chunks,
-                                 num_src_chunks))) {
-        patch_data[i] = MakePatch(src, tgt_chunks+i, patch_size+i);
+          (src = FindChunkByName(tgt_chunks[i].filename, src_chunks, num_src_chunks))) {
+        patch_data[i] = MakePatch(src, tgt_chunks + i, patch_size + i, nullptr);
       } else {
-        patch_data[i] = MakePatch(src_chunks, tgt_chunks+i, patch_size+i);
+        patch_data[i] = MakePatch(src_chunks, tgt_chunks + i, patch_size + i, &bsdiff_cache);
       }
     } else {
       if (i == 1 && bonus_data) {
         printf("  using %zu bytes of bonus data for chunk %d\n", bonus_size, i);
-        src_chunks[i].data = static_cast<unsigned char*>(realloc(src_chunks[i].data,
-            src_chunks[i].len + bonus_size));
-        memcpy(src_chunks[i].data+src_chunks[i].len, bonus_data, bonus_size);
+        src_chunks[i].data =
+            static_cast<unsigned char*>(realloc(src_chunks[i].data, src_chunks[i].len + bonus_size));
+        memcpy(src_chunks[i].data + src_chunks[i].len, bonus_data, bonus_size);
         src_chunks[i].len += bonus_size;
-     }
+      }
 
-      patch_data[i] = MakePatch(src_chunks+i, tgt_chunks+i, patch_size+i);
+      patch_data[i] = MakePatch(src_chunks + i, tgt_chunks + i, patch_size + i, nullptr);
     }
-    printf("patch %3d is %zu bytes (of %zu)\n",
-           i, patch_size[i], tgt_chunks[i].source_len);
+    printf("patch %3d is %zu bytes (of %zu)\n", i, patch_size[i], tgt_chunks[i].source_len);
   }
+  free(bsdiff_cache);
+  free(src_chunks);
 
   // Figure out how big the imgdiff file header is going to be, so
   // that we can correctly compute the offset of each bsdiff patch
@@ -1080,6 +1072,7 @@ int main(int argc, char** argv) {
     }
   }
 
+  free(tgt_chunks);
   free(patch_data);
   free(patch_size);