applypatch changes for patching recovery image

Make some changes needed to applypatch in order to store the recovery
image in the system partition as a binary patch relative to the boot
image:

  - make applypatch use shared libraries, so it's smaller.  It will
    need to be on the main system so it can install the recovery
    image.  Make an applypatch_static binary for use in recovery
    packages (still needed for updating cupcake devices to donut).

  - output the results of patching to an in-memory buffer and write
    that to the partition; there's no convenient /tmp for us to us.
    (This should be basically a no-op in recovery, since /tmp is a
    ramdisk anyway.)

core/Makefile

@@ -788,6 +788,7 @@ endef
 
 built_ota_tools := \
 	$(call intermediates-dir-for,EXECUTABLES,applypatch)/applypatch \
+	$(call intermediates-dir-for,EXECUTABLES,applypatch_static)/applypatch_static \
 	$(call intermediates-dir-for,EXECUTABLES,check_prereq)/check_prereq \
 	$(call intermediates-dir-for,EXECUTABLES,updater)/updater
 $(BUILT_TARGET_FILES_PACKAGE): PRIVATE_OTA_TOOLS := $(built_ota_tools)

tools/applypatch/Android.mk

@@ -29,11 +29,19 @@ include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES := main.c
 LOCAL_MODULE := applypatch
+LOCAL_STATIC_LIBRARIES += libapplypatch libmtdutils libmincrypt libbz
+LOCAL_SHARED_LIBRARIES += libz libcutils libstdc++ libc
+
+include $(BUILD_EXECUTABLE)
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := main.c
+LOCAL_MODULE := applypatch_static
 LOCAL_FORCE_STATIC_EXECUTABLE := true
 LOCAL_MODULE_TAGS := eng
-LOCAL_STATIC_LIBRARIES += libapplypatch
+LOCAL_STATIC_LIBRARIES += libapplypatch libmtdutils libmincrypt libbz
-LOCAL_STATIC_LIBRARIES += libmtdutils libmincrypt libbz libz
+LOCAL_STATIC_LIBRARIES += libz libcutils libstdc++ libc
-LOCAL_STATIC_LIBRARIES += libcutils libstdc++ libc
 
 include $(BUILD_EXECUTABLE)
 

tools/applypatch/applypatch.c

@@ -282,9 +282,10 @@ int SaveFileContents(const char* filename, FileContents file) {
   return 0;
 }
 
-// Copy the contents of source_file to target_mtd partition, a string
+// Write a memory buffer to target_mtd partition, a string of the form
-// of the form "MTD:<partition>[:...]".  Return 0 on success.
+// "MTD:<partition>[:...]".  Return 0 on success.
-int CopyToMTDPartition(const char* source_file, const char* target_mtd) {
+int WriteToMTDPartition(unsigned char* data, size_t len,
+                        const char* target_mtd) {
   char* partition = strchr(target_mtd, ':');
   if (partition == NULL) {
     fprintf(stderr, "bad MTD target name \"%s\"\n", target_mtd);
@@ -298,13 +299,6 @@ int CopyToMTDPartition(const char* source_file, const char* target_mtd) {
   if (end != NULL)
     *end = '\0';
 
-  FILE* f = fopen(source_file, "rb");
-  if (f == NULL) {
-    fprintf(stderr, "failed to open %s for reading: %s\n",
-            source_file, strerror(errno));
-    return -1;
-  }
-
   if (!mtd_partitions_scanned) {
     mtd_scan_partitions();
     mtd_partitions_scanned = 1;
@@ -323,20 +317,14 @@ int CopyToMTDPartition(const char* source_file, const char* target_mtd) {
     return -1;
   }
 
-  const int buffer_size = 4096;
+  size_t written = mtd_write_data(ctx, (char*)data, len);
-  char buffer[buffer_size];
+  if (written != len) {
-  size_t read;
+    fprintf(stderr, "only wrote %d of %d bytes to MTD %s\n",
-  while ((read = fread(buffer, 1, buffer_size, f)) > 0) {
+            written, len, partition);
-    size_t written = mtd_write_data(ctx, buffer, read);
+    mtd_write_close(ctx);
-    if (written != read) {
+    return -1;
-      fprintf(stderr, "only wrote %d of %d bytes to MTD %s\n",
-              written, read, partition);
-      mtd_write_close(ctx);
-      return -1;
-    }
   }
 
-  fclose(f);
   if (mtd_erase_blocks(ctx, -1) < 0) {
     fprintf(stderr, "error finishing mtd write of %s\n", partition);
     mtd_write_close(ctx);
@@ -476,6 +464,26 @@ int ShowLicenses() {
   return 0;
 }
 
+size_t FileSink(unsigned char* data, size_t len, void* token) {
+  return fwrite(data, 1, len, (FILE*)token);
+}
+
+typedef struct {
+  unsigned char* buffer;
+  size_t size;
+  size_t pos;
+} MemorySinkInfo;
+
+size_t MemorySink(unsigned char* data, size_t len, void* token) {
+  MemorySinkInfo* msi = (MemorySinkInfo*)token;
+  if (msi->size - msi->pos < len) {
+    return -1;
+  }
+  memcpy(msi->buffer + msi->pos, data, len);
+  msi->pos += len;
+  return len;
+}
+
 // Return the amount of free space (in bytes) on the filesystem
 // containing filename.  filename must exist.  Return -1 on error.
 size_t FreeSpaceForFile(const char* filename) {
@@ -720,19 +728,36 @@ int applypatch(int argc, char** argv) {
   }
 
   char* outname = NULL;
+  FILE* output = NULL;
+  MemorySinkInfo msi;
+  SinkFn sink = NULL;
+  void* token = NULL;
   if (strncmp(target_filename, "MTD:", 4) == 0) {
-    outname = MTD_TARGET_TEMP_FILE;
+    // We store the decoded output in memory.
+    msi.buffer = malloc(target_size);
+    if (msi.buffer == NULL) {
+      fprintf(stderr, "failed to alloc %ld bytes for output\n",
+              (long)target_size);
+      return 1;
+    }
+    msi.pos = 0;
+    msi.size = target_size;
+    sink = MemorySink;
+    token = &msi;
   } else {
     // We write the decoded output to "<tgt-file>.patch".
     outname = (char*)malloc(strlen(target_filename) + 10);
     strcpy(outname, target_filename);
     strcat(outname, ".patch");
-  }
+
-  FILE* output = fopen(outname, "wb");
+    output = fopen(outname, "wb");
-  if (output == NULL) {
+    if (output == NULL) {
-    fprintf(stderr, "failed to open output file %s: %s\n",
+      fprintf(stderr, "failed to open output file %s: %s\n",
-            outname, strerror(errno));
+              outname, strerror(errno));
-    return 1;
+      return 1;
+    }
+    sink = FileSink;
+    token = output;
   }
 
 #define MAX_HEADER_LENGTH 8
@@ -759,7 +784,7 @@ int applypatch(int argc, char** argv) {
   } else if (header_bytes_read >= 8 &&
              memcmp(header, "BSDIFF40", 8) == 0) {
     int result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size,
-                                  patch_filename, 0, output, &ctx);
+                                  patch_filename, 0, sink, token, &ctx);
     if (result != 0) {
       fprintf(stderr, "ApplyBSDiffPatch failed\n");
       return result;
@@ -768,7 +793,7 @@ int applypatch(int argc, char** argv) {
              memcmp(header, "IMGDIFF", 7) == 0 &&
              (header[7] == '1' || header[7] == '2')) {
     int result = ApplyImagePatch(source_to_use->data, source_to_use->size,
-                                 patch_filename, output, &ctx);
+                                 patch_filename, sink, token, &ctx);
     if (result != 0) {
       fprintf(stderr, "ApplyImagePatch failed\n");
       return result;
@@ -778,9 +803,11 @@ int applypatch(int argc, char** argv) {
     return 1;
   }
 
-  fflush(output);
+  if (output != NULL) {
-  fsync(fileno(output));
+    fflush(output);
-  fclose(output);
+    fsync(fileno(output));
+    fclose(output);
+  }
 
   const uint8_t* current_target_sha1 = SHA_final(&ctx);
   if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
@@ -788,13 +815,13 @@ int applypatch(int argc, char** argv) {
     return 1;
   }
 
-  if (strcmp(outname, MTD_TARGET_TEMP_FILE) == 0) {
+  if (output == NULL) {
     // Copy the temp file to the MTD partition.
-    if (CopyToMTDPartition(outname, target_filename) != 0) {
+    if (WriteToMTDPartition(msi.buffer, msi.pos, target_filename) != 0) {
-      fprintf(stderr, "copy of %s to %s failed\n", outname, target_filename);
+      fprintf(stderr, "write of patched data to %s failed\n", target_filename);
       return 1;
     }
-    unlink(outname);
+    free(msi.buffer);
   } else {
     // Give the .patch file the same owner, group, and mode of the
     // original source file.

tools/applypatch/applypatch.h

@@ -39,10 +39,7 @@ typedef struct _FileContents {
 // and use it as the source instead.
 #define CACHE_TEMP_SOURCE "/cache/saved.file"
 
-// When writing to an MTD partition, we first put the output in this
+typedef size_t (*SinkFn)(unsigned char*, size_t, void*);
-// temp file, then copy it to the partition once the patching is
-// finished (and the target sha1 verified).
-#define MTD_TARGET_TEMP_FILE "/tmp/mtd-temp"
 
 // applypatch.c
 size_t FreeSpaceForFile(const char* filename);
@@ -52,15 +49,15 @@ int applypatch(int argc, char** argv);
 void ShowBSDiffLicense();
 int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size,
                      const char* patch_filename, ssize_t offset,
-                     FILE* output, SHA_CTX* ctx);
+                     SinkFn sink, void* token, SHA_CTX* ctx);
 int ApplyBSDiffPatchMem(const unsigned char* old_data, ssize_t old_size,
                         const char* patch_filename, ssize_t patch_offset,
                         unsigned char** new_data, ssize_t* new_size);
 
 // imgpatch.c
 int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
-                     const char* patch_filename,
+                    const char* patch_filename,
-                     FILE* output, SHA_CTX* ctx);
+                    SinkFn sink, void* token, SHA_CTX* ctx);
 
 // freecache.c
 int MakeFreeSpaceOnCache(size_t bytes_needed);

tools/applypatch/bsdiff.c

@@ -84,7 +84,7 @@ static off_t offtin(u_char *buf)
 
 int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size,
                      const char* patch_filename, ssize_t patch_offset,
-                     FILE* output, SHA_CTX* ctx) {
+                     SinkFn sink, void* token, SHA_CTX* ctx) {
 
   unsigned char* new_data;
   ssize_t new_size;
@@ -93,7 +93,7 @@ int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size,
     return -1;
   }
 
-  if (fwrite(new_data, 1, new_size, output) < new_size) {
+  if (sink(new_data, new_size, token) < new_size) {
     fprintf(stderr, "short write of output: %d (%s)\n", errno, strerror(errno));
     return 1;
   }

tools/applypatch/imgpatch.c

@@ -37,7 +37,7 @@
  */
 int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
                     const char* patch_filename,
-                    FILE* output, SHA_CTX* ctx) {
+                    SinkFn sink, void* token, SHA_CTX* ctx) {
   FILE* f;
   if ((f = fopen(patch_filename, "rb")) == NULL) {
     fprintf(stderr, "failed to open patch file\n");
@@ -86,7 +86,7 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
 
       ApplyBSDiffPatch(old_data + src_start, src_len,
                        patch_filename, patch_offset,
-                       output, ctx);
+                       sink, token, ctx);
     } else if (type == CHUNK_GZIP) {
       // This branch is basically a duplicate of the CHUNK_DEFLATE
       // branch, with a bit of extra processing for the gzip header
@@ -178,7 +178,7 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
       // Now compress the target data and append it to the output.
 
       // start with the gzip header.
-      fwrite(gzip+64, 1, gzip_header_len, output);
+      sink(gzip+64, gzip_header_len, token);
       SHA_update(ctx, gzip+64, gzip_header_len);
 
       // we're done with the expanded_source data buffer, so we'll
@@ -207,7 +207,7 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
         ret = deflate(&strm, Z_FINISH);
         size_t have = temp_size - strm.avail_out;
 
-        if (fwrite(temp_data, 1, have, output) != have) {
+        if (sink(temp_data, have, token) != have) {
           fprintf(stderr, "failed to write %d compressed bytes to output\n",
                   have);
           return -1;
@@ -217,7 +217,7 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
       deflateEnd(&strm);
 
       // lastly, the gzip footer.
-      fwrite(gzip+64+gzip_header_len, 1, 8, output);
+      sink(gzip+64+gzip_header_len, 8, token);
       SHA_update(ctx, gzip+64+gzip_header_len, 8);
 
       free(temp_data);
@@ -240,7 +240,7 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
           return -1;
       }
       SHA_update(ctx, temp, data_len);
-      if (fwrite(temp, 1, data_len, output) != data_len) {
+      if (sink(temp, data_len, token) != data_len) {
           fprintf(stderr, "failed to write chunk %d raw data\n", i);
           return -1;
       }
@@ -343,7 +343,7 @@ int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
         ret = deflate(&strm, Z_FINISH);
         size_t have = temp_size - strm.avail_out;
 
-        if (fwrite(temp_data, 1, have, output) != have) {
+        if (sink(temp_data, have, token) != have) {
           fprintf(stderr, "failed to write %d compressed bytes to output\n",
                   have);
           return -1;

tools/releasetools/amend_generator.py

@@ -94,13 +94,13 @@ class AmendGenerator(object):
     for i in sha1:
       out.append(" " + i)
     self.script.append("".join(out))
-    self.included_files.add("applypatch")
+    self.included_files.add(("applypatch_static", "applypatch"))
 
   def CacheFreeSpaceCheck(self, amount):
     """Check that there's at least 'amount' space that can be made
     available on /cache."""
     self.script.append("run_program PACKAGE:applypatch -s %d" % (amount,))
-    self.included_files.add("applypatch")
+    self.included_files.add(("applypatch_static", "applypatch"))
 
   def Mount(self, kind, what, path):
     # no-op; amend uses it's 'roots' system to automatically mount
@@ -155,7 +155,7 @@ class AmendGenerator(object):
          (srcfile, tgtfile, tgtsha1, tgtsize)) +
         " ".join(["%s:%s" % patchpairs[i:i+2]
                   for i in range(0, len(patchpairs), 2)]))
-    self.included_files.add("applypatch")
+    self.included_files.add(("applypatch_static", "applypatch"))
 
   def WriteFirmwareImage(self, kind, fn):
     """Arrange to update the given firmware image (kind must be
@@ -195,11 +195,16 @@ class AmendGenerator(object):
     common.ZipWriteStr(output_zip, "META-INF/com/google/android/update-script",
                        "\n".join(self.script) + "\n")
     for i in self.included_files:
+      if isinstance(i, tuple):
+        sourcefn, targetfn = i
+      else:
+        sourcefn = i
+        targetfn = i
       try:
         if input_path is None:
-          data = input_zip.read(os.path.join("OTA/bin", i))
+          data = input_zip.read(os.path.join("OTA/bin", sourcefn))
         else:
-          data = open(os.path.join(input_path, i)).read()
+          data = open(os.path.join(input_path, sourcefn)).read()
-        common.ZipWriteStr(output_zip, i, data, perms=0755)
+        common.ZipWriteStr(output_zip, targetfn, data, perms=0755)
       except (IOError, KeyError), e:
         raise ExternalError("unable to include binary %s: %s" % (i, e))