1 files changed, 406 insertions, 650 deletions

diff --git a/applypatch/applypatch.cpp b/applypatch/applypatch.cpp
index c2fe11b3b..54c37eb34 100644
--- a/applypatch/applypatch.cpp
+++ b/applypatch/applypatch.cpp
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#include "applypatch/applypatch.h"
+
 #include <errno.h>
 #include <fcntl.h>
 #include <libgen.h>
@@ -27,72 +29,65 @@
 
 #include <memory>
 #include <string>
+#include <utility>
+#include <vector>
 
+#include <android-base/logging.h>
+#include <android-base/parseint.h>
 #include <android-base/strings.h>
+#include <openssl/sha.h>
 
-#include "openssl/sha.h"
-#include "applypatch.h"
 #include "bmlutils/bmlutils.h"
 #include "mtdutils/mtdutils.h"
+
 #include "edify/expr.h"
 #include "ota_io.h"
 #include "print_sha1.h"
 
-static int LoadPartitionContents(const char* filename, FileContents* file);
+static int LoadPartitionContents(const std::string& filename, FileContents* file);
 static ssize_t FileSink(const unsigned char* data, ssize_t len, void* token);
-static int GenerateTarget(FileContents* source_file,
-                          const Value* source_patch_value,
-                          FileContents* copy_file,
-                          const Value* copy_patch_value,
-                          const char* source_filename,
-                          const char* target_filename,
-                          const uint8_t target_sha1[SHA_DIGEST_LENGTH],
-                          size_t target_size,
-                          const Value* bonus_data);
+static int GenerateTarget(const FileContents& source_file, const std::unique_ptr<Value>& patch,
+                          const std::string& target_filename,
+                          const uint8_t target_sha1[SHA_DIGEST_LENGTH], const Value* bonus_data);
 
 static bool mtd_partitions_scanned = false;
 
-// Read a file into memory; store the file contents and associated
-// metadata in *file.
-//
+// Read a file into memory; store the file contents and associated metadata in *file.
 // Return 0 on success.
 int LoadFileContents(const char* filename, FileContents* file) {
-    // A special 'filename' beginning with "MTD:" or "EMMC:" means to
-    // load the contents of a partition.
-    if (strncmp(filename, "MTD:", 4) == 0 ||
-        strncmp(filename, "EMMC:", 5) == 0 ||
-        strncmp(filename, "BML:", 4) == 0) {
-        return LoadPartitionContents(filename, file);
-    }
-
-    if (stat(filename, &file->st) != 0) {
-        printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
-        return -1;
-    }
+  // A special 'filename' beginning with "MTD:" or "EMMC:" means to
+  // load the contents of a partition.
+  if (strncmp(filename, "MTD:", 4) == 0 ||
+    strncmp(filename, "EMMC:", 5) == 0 ||
+    strncmp(filename, "BML:", 4) == 0) {
+    return LoadPartitionContents(filename, file);
+  }
+
+  if (stat(filename, &file->st) == -1) {
+    printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
+    return -1;
+  }
 
-    std::vector<unsigned char> data(file->st.st_size);
-    FILE* f = ota_fopen(filename, "rb");
-    if (f == NULL) {
-        printf("failed to open \"%s\": %s\n", filename, strerror(errno));
-        return -1;
-    }
+  std::vector<unsigned char> data(file->st.st_size);
+  unique_file f(ota_fopen(filename, "rb"));
+  if (!f) {
+    printf("failed to open \"%s\": %s\n", filename, strerror(errno));
+    return -1;
+  }
 
-    size_t bytes_read = ota_fread(data.data(), 1, data.size(), f);
-    if (bytes_read != data.size()) {
-        printf("short read of \"%s\" (%zu bytes of %zd)\n", filename, bytes_read, data.size());
-        ota_fclose(f);
-        return -1;
-    }
-    ota_fclose(f);
-    file->data = std::move(data);
-    SHA1(file->data.data(), file->data.size(), file->sha1);
-    return 0;
+  size_t bytes_read = ota_fread(data.data(), 1, data.size(), f.get());
+  if (bytes_read != data.size()) {
+    printf("short read of \"%s\" (%zu bytes of %zu)\n", filename, bytes_read, data.size());
+    return -1;
+  }
+  file->data = std::move(data);
+  SHA1(file->data.data(), file->data.size(), file->sha1);
+  return 0;
 }
 
-// Load the contents of an MTD or EMMC partition into the provided
+// Load the contents of an EMMC partition into the provided
 // FileContents.  filename should be a string of the form
-// "MTD:<partition_name>:<size_1>:<sha1_1>:<size_2>:<sha1_2>:..."  (or
-// "EMMC:<partition_device>:...").  The smallest size_n bytes for
+// "EMMC:<partition_device>:...".  The smallest size_n bytes for
 // which that prefix of the partition contents has the corresponding
 // sha1 hash will be loaded.  It is acceptable for a size value to be
 // repeated with different sha1s.  Will return 0 on success.
@@ -106,223 +101,166 @@ int LoadFileContents(const char* filename, FileContents* file) {
 // to find one of those hashes.
 enum PartitionType { MTD, EMMC };
 
-static int LoadPartitionContents(const char* filename, FileContents* file) {
-    std::string copy(filename);
-    std::vector<std::string> pieces = android::base::Split(copy, ":");
-    if (pieces.size() < 4 || pieces.size() % 2 != 0) {
-        printf("LoadPartitionContents called with bad filename (%s)\n", filename);
-        return -1;
-    }
-
-    enum PartitionType type;
-    if (pieces[0] == "MTD") {
-        type = MTD;
-    } else if (pieces[0] == "EMMC") {
-        type = EMMC;
-    } else if (pieces[0] == "BML") {
-        type = EMMC;
-    } else {
-        printf("LoadPartitionContents called with bad filename (%s)\n", filename);
+static int LoadPartitionContents(const std::string& filename, FileContents* file) {
+  std::vector<std::string> pieces = android::base::Split(filename, ":");
+  if (pieces.size() < 4 || pieces.size() % 2 != 0) {
+    printf("LoadPartitionContents called with bad filename \"%s\"\n", filename.c_str());
+    return -1;
+  }
+
+  enum PartitionType type;
+  if (pieces[0] == "MTD") {
+    type = MTD;
+  } else if (pieces[0] == "EMMC") {
+    type = EMMC;
+  } else if (pieces[0] == "BML") {
+    type = EMMC;
+  } else {
+    printf("LoadPartitionContents called with bad filename (%s)\n", filename.c_str());
+    return -1;
+  }
+
+  size_t pair_count = (pieces.size() - 2) / 2;  // # of (size, sha1) pairs in filename
+  std::vector<std::pair<size_t, std::string>> pairs;
+  for (size_t i = 0; i < pair_count; ++i) {
+    size_t size;
+    if (!android::base::ParseUint(pieces[i * 2 + 2], &size) || size == 0) {
+      printf("LoadPartitionContents called with bad size \"%s\"\n", pieces[i * 2 + 2].c_str());
+      return -1;
+    }
+    pairs.push_back({ size, pieces[i * 2 + 3] });
+  }
+
+  // Sort the pairs array so that they are in order of increasing size.
+  std::sort(pairs.begin(), pairs.end());
+
+  const char* partition = pieces[1].c_str();
+  unique_file dev(ota_fopen(partition, "rb"));
+  if (!dev) {
+    printf("failed to open emmc partition \"%s\": %s\n", partition, strerror(errno));
+    return -1;
+  }
+
+  SHA_CTX sha_ctx;
+  SHA1_Init(&sha_ctx);
+
+  // Allocate enough memory to hold the largest size.
+  std::vector<unsigned char> buffer(pairs[pair_count - 1].first);
+  unsigned char* buffer_ptr = buffer.data();
+  size_t buffer_size = 0;  // # bytes read so far
+  bool found = false;
+
+  for (const auto& pair : pairs) {
+    size_t current_size = pair.first;
+    const std::string& current_sha1 = pair.second;
+
+    // Read enough additional bytes to get us up to the next size. (Again,
+    // we're trying the possibilities in order of increasing size).
+    size_t next = current_size - buffer_size;
+    if (next > 0) {
+      size_t read = ota_fread(buffer_ptr, 1, next, dev.get());
+      if (next != read) {
+        printf("short read (%zu bytes of %zu) for partition \"%s\"\n", read, next, partition);
         return -1;
+      }
+      SHA1_Update(&sha_ctx, buffer_ptr, read);
+      buffer_size += read;
+      buffer_ptr += read;
     }
-    const char* partition = pieces[1].c_str();
 
     if (pieces[0] == "BML") {
-        if (strcmp(partition, "boot") == 0) {
-            partition = BOARD_BML_BOOT;
-        } else if (strcmp(partition, "recovery") == 0) {
-            partition = BOARD_BML_RECOVERY;
-        }
+      if (strcmp(partition, "boot") == 0) {
+        partition = BOARD_BML_BOOT;
+      } else if (strcmp(partition, "recovery") == 0) {
+        partition = BOARD_BML_RECOVERY;
+      }
     }
 
-    size_t pairs = (pieces.size() - 2) / 2;    // # of (size, sha1) pairs in filename
-    std::vector<size_t> index(pairs);
-    std::vector<size_t> size(pairs);
-    std::vector<std::string> sha1sum(pairs);
-
-    for (size_t i = 0; i < pairs; ++i) {
-        size[i] = strtol(pieces[i*2+2].c_str(), NULL, 10);
-        if (size[i] == 0) {
-            printf("LoadPartitionContents called with bad size (%s)\n", filename);
-            return -1;
-        }
-        sha1sum[i] = pieces[i*2+3].c_str();
-        index[i] = i;
-    }
-
-    // Sort the index[] array so it indexes the pairs in order of increasing size.
-    sort(index.begin(), index.end(),
-        [&](const size_t& i, const size_t& j) {
-            return (size[i] < size[j]);
-        }
-    );
-
-    MtdReadContext* ctx = NULL;
-    FILE* dev = NULL;
-
-    switch (type) {
-        case MTD: {
-            if (!mtd_partitions_scanned) {
-                mtd_scan_partitions();
-                mtd_partitions_scanned = true;
-            }
-
-            const MtdPartition* mtd = mtd_find_partition_by_name(partition);
-            if (mtd == NULL) {
-                printf("mtd partition \"%s\" not found (loading %s)\n", partition, filename);
-                return -1;
-            }
+    // Duplicate the SHA context and finalize the duplicate so we can
+    // check it against this pair's expected hash.
+    SHA_CTX temp_ctx;
+    memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX));
+    uint8_t sha_so_far[SHA_DIGEST_LENGTH];
+    SHA1_Final(sha_so_far, &temp_ctx);
 
-            ctx = mtd_read_partition(mtd);
-            if (ctx == NULL) {
-                printf("failed to initialize read of mtd partition \"%s\"\n", partition);
-                return -1;
-            }
-            break;
-        }
-
-        case EMMC:
-            dev = ota_fopen(partition, "rb");
-            if (dev == NULL) {
-                printf("failed to open emmc partition \"%s\": %s\n", partition, strerror(errno));
-                return -1;
-            }
-    }
-
-    SHA_CTX sha_ctx;
-    SHA1_Init(&sha_ctx);
     uint8_t parsed_sha[SHA_DIGEST_LENGTH];
-
-    // Allocate enough memory to hold the largest size.
-    std::vector<unsigned char> data(size[index[pairs-1]]);
-    char* p = reinterpret_cast<char*>(data.data());
-    size_t data_size = 0;                // # bytes read so far
-    bool found = false;
-
-    for (size_t i = 0; i < pairs; ++i) {
-        // Read enough additional bytes to get us up to the next size. (Again,
-        // we're trying the possibilities in order of increasing size).
-        size_t next = size[index[i]] - data_size;
-        if (next > 0) {
-            size_t read = 0;
-            switch (type) {
-                case MTD:
-                    read = mtd_read_data(ctx, p, next);
-                    break;
-
-                case EMMC:
-                    read = ota_fread(p, 1, next, dev);
-                    break;
-            }
-            if (next != read) {
-                printf("short read (%zu bytes of %zu) for partition \"%s\"\n",
-                       read, next, partition);
-                return -1;
-            }
-            SHA1_Update(&sha_ctx, p, read);
-            data_size += read;
-            p += read;
-        }
-
-        // Duplicate the SHA context and finalize the duplicate so we can
-        // check it against this pair's expected hash.
-        SHA_CTX temp_ctx;
-        memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX));
-        uint8_t sha_so_far[SHA_DIGEST_LENGTH];
-        SHA1_Final(sha_so_far, &temp_ctx);
-
-        if (ParseSha1(sha1sum[index[i]].c_str(), parsed_sha) != 0) {
-            printf("failed to parse sha1 %s in %s\n", sha1sum[index[i]].c_str(), filename);
-            return -1;
-        }
-
-        if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_LENGTH) == 0) {
-            // we have a match.  stop reading the partition; we'll return
-            // the data we've read so far.
-            printf("partition read matched size %zu sha %s\n",
-                   size[index[i]], sha1sum[index[i]].c_str());
-            found = true;
-            break;
-        }
+    if (ParseSha1(current_sha1.c_str(), parsed_sha) != 0) {
+      printf("failed to parse SHA-1 %s in %s\n", current_sha1.c_str(), filename.c_str());
+      return -1;
     }
 
-    switch (type) {
-        case MTD:
-            mtd_read_close(ctx);
-            break;
-
-        case EMMC:
-            ota_fclose(dev);
-            break;
+    if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_LENGTH) == 0) {
+      // We have a match. Stop reading the partition; we'll return the data we've read so far.
+      printf("partition read matched size %zu SHA-1 %s\n", current_size, current_sha1.c_str());
+      found = true;
+      break;
     }
+  }
 
+  if (!found) {
+    // Ran off the end of the list of (size, sha1) pairs without finding a match.
+    printf("contents of partition \"%s\" didn't match %s\n", partition, filename.c_str());
+    return -1;
+  }
 
-    if (!found) {
-        // Ran off the end of the list of (size,sha1) pairs without finding a match.
-        printf("contents of partition \"%s\" didn't match %s\n", partition, filename);
-        return -1;
-    }
-
-    SHA1_Final(file->sha1, &sha_ctx);
+  SHA1_Final(file->sha1, &sha_ctx);
 
-    data.resize(data_size);
-    file->data = std::move(data);
-    // Fake some stat() info.
-    file->st.st_mode = 0644;
-    file->st.st_uid = 0;
-    file->st.st_gid = 0;
+  buffer.resize(buffer_size);
+  file->data = std::move(buffer);
+  // Fake some stat() info.
+  file->st.st_mode = 0644;
+  file->st.st_uid = 0;
+  file->st.st_gid = 0;
 
-    return 0;
+  return 0;
 }
 
-
 // Save the contents of the given FileContents object under the given
 // filename.  Return 0 on success.
 int SaveFileContents(const char* filename, const FileContents* file) {
-    int fd = ota_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, S_IRUSR | S_IWUSR);
-    if (fd < 0) {
-        printf("failed to open \"%s\" for write: %s\n", filename, strerror(errno));
-        return -1;
-    }
+  unique_fd fd(ota_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, S_IRUSR | S_IWUSR));
+  if (fd == -1) {
+    printf("failed to open \"%s\" for write: %s\n", filename, strerror(errno));
+    return -1;
+  }
 
-    ssize_t bytes_written = FileSink(file->data.data(), file->data.size(), &fd);
-    if (bytes_written != static_cast<ssize_t>(file->data.size())) {
-        printf("short write of \"%s\" (%zd bytes of %zu) (%s)\n",
-               filename, bytes_written, file->data.size(), strerror(errno));
-        ota_close(fd);
-        return -1;
-    }
-    if (ota_fsync(fd) != 0) {
-        printf("fsync of \"%s\" failed: %s\n", filename, strerror(errno));
-        return -1;
-    }
-    if (ota_close(fd) != 0) {
-        printf("close of \"%s\" failed: %s\n", filename, strerror(errno));
-        return -1;
-    }
+  ssize_t bytes_written = FileSink(file->data.data(), file->data.size(), &fd);
+  if (bytes_written != static_cast<ssize_t>(file->data.size())) {
+    printf("short write of \"%s\" (%zd bytes of %zu): %s\n", filename, bytes_written,
+           file->data.size(), strerror(errno));
+    return -1;
+  }
+  if (ota_fsync(fd) != 0) {
+    printf("fsync of \"%s\" failed: %s\n", filename, strerror(errno));
+    return -1;
+  }
+  if (ota_close(fd) != 0) {
+    printf("close of \"%s\" failed: %s\n", filename, strerror(errno));
+    return -1;
+  }
 
-    if (chmod(filename, file->st.st_mode) != 0) {
-        printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno));
-        return -1;
-    }
-    if (chown(filename, file->st.st_uid, file->st.st_gid) != 0) {
-        printf("chown of \"%s\" failed: %s\n", filename, strerror(errno));
-        return -1;
-    }
+  if (chmod(filename, file->st.st_mode) != 0) {
+    printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno));
+    return -1;
+  }
+  if (chown(filename, file->st.st_uid, file->st.st_gid) != 0) {
+    printf("chown of \"%s\" failed: %s\n", filename, strerror(errno));
+    return -1;
+  }
 
-    return 0;
+  return 0;
 }
 
 // Write a memory buffer to 'target' partition, a string of the form
-// "MTD:<partition>[:...]" or "EMMC:<partition_device>[:...]". The target name
+// "EMMC:<partition_device>[:...]". The target name
 // might contain multiple colons, but WriteToPartition() only uses the first
 // two and ignores the rest. Return 0 on success.
-int WriteToPartition(const unsigned char* data, size_t len, const char* target) {
+int WriteToPartition(const unsigned char* data, size_t len, const std::string& target) {
     std::string copy(target);
     std::vector<std::string> pieces = android::base::Split(copy, ":");
 
     if (pieces.size() < 2) {
-        printf("WriteToPartition called with bad target (%s)\n", target);
+        printf("WriteToPartition called with bad target (%s)\n", target.c_str());
         return -1;
     }
 
@@ -334,7 +272,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target)
     } else if (pieces[0] == "BML") {
         type = EMMC;
     } else {
-        printf("WriteToPartition called with bad target (%s)\n", target);
+        printf("WriteToPartition called with bad target (%s)\n", target.c_str());
         return -1;
     }
 
@@ -358,7 +296,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target)
     }
 
     if (partition == NULL) {
-        printf("bad partition target name \"%s\"\n", target);
+        printf("bad partition target name \"%s\"\n", target.c_str());
         return -1;
     }
 
@@ -404,7 +342,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target)
         case EMMC: {
             size_t start = 0;
             bool success = false;
-            int fd = ota_open(partition, O_RDWR | O_SYNC);
+            unique_fd fd(ota_open(partition, O_RDWR | O_SYNC));
             if (fd < 0) {
                 printf("failed to open %s: %s\n", partition, strerror(errno));
                 return -1;
@@ -434,7 +372,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target)
                    printf("failed to close %s (%s)\n", partition, strerror(errno));
                    return -1;
                 }
-                fd = ota_open(partition, O_RDONLY);
+                unique_fd fd(ota_open(partition, O_RDONLY));
                 if (fd < 0) {
                    printf("failed to reopen %s for verify (%s)\n", partition, strerror(errno));
                    return -1;
@@ -443,7 +381,7 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target)
                 // Drop caches so our subsequent verification read
                 // won't just be reading the cache.
                 sync();
-                int dc = ota_open("/proc/sys/vm/drop_caches", O_WRONLY);
+                unique_fd dc(ota_open("/proc/sys/vm/drop_caches", O_WRONLY));
                 if (TEMP_FAILURE_RETRY(ota_write(dc, "3\n", 2)) == -1) {
                     printf("write to /proc/sys/vm/drop_caches failed: %s\n", strerror(errno));
                 } else {
@@ -513,7 +451,6 @@ int WriteToPartition(const unsigned char* data, size_t len, const char* target)
     return 0;
 }
 
-
 // Take a string 'str' of 40 hex digits and parse it into the 20
 // byte array 'digest'.  'str' may contain only the digest or be of
 // the form "<digest>:<anything>".  Return 0 on success, -1 on any
@@ -546,52 +483,47 @@ int ParseSha1(const char* str, uint8_t* digest) {
 // Search an array of sha1 strings for one matching the given sha1.
 // Return the index of the match on success, or -1 if no match is
 // found.
-int FindMatchingPatch(uint8_t* sha1, char* const * const patch_sha1_str,
-                      int num_patches) {
+static int FindMatchingPatch(uint8_t* sha1, const std::vector<std::string>& patch_sha1_str) {
+  for (size_t i = 0; i < patch_sha1_str.size(); ++i) {
     uint8_t patch_sha1[SHA_DIGEST_LENGTH];
-    for (int i = 0; i < num_patches; ++i) {
-        if (ParseSha1(patch_sha1_str[i], patch_sha1) == 0 &&
-            memcmp(patch_sha1, sha1, SHA_DIGEST_LENGTH) == 0) {
-            return i;
-        }
+    if (ParseSha1(patch_sha1_str[i].c_str(), patch_sha1) == 0 &&
+        memcmp(patch_sha1, sha1, SHA_DIGEST_LENGTH) == 0) {
+      return i;
     }
-    return -1;
+  }
+  return -1;
 }
 
 // Returns 0 if the contents of the file (argv[2]) or the cached file
 // match any of the sha1's on the command line (argv[3:]).  Returns
 // nonzero otherwise.
-int applypatch_check(const char* filename, int num_patches,
-                     char** const patch_sha1_str) {
-    FileContents file;
-
-    // It's okay to specify no sha1s; the check will pass if the
-    // LoadFileContents is successful.  (Useful for reading
-    // partitions, where the filename encodes the sha1s; no need to
-    // check them twice.)
-    if (LoadFileContents(filename, &file) != 0 ||
-        (num_patches > 0 &&
-         FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0)) {
-        printf("file \"%s\" doesn't have any of expected "
-               "sha1 sums; checking cache\n", filename);
-
-        // If the source file is missing or corrupted, it might be because
-        // we were killed in the middle of patching it.  A copy of it
-        // should have been made in CACHE_TEMP_SOURCE.  If that file
-        // exists and matches the sha1 we're looking for, the check still
-        // passes.
-
-        if (LoadFileContents(CACHE_TEMP_SOURCE, &file) != 0) {
-            printf("failed to load cache file\n");
-            return 1;
-        }
-
-        if (FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0) {
-            printf("cache bits don't match any sha1 for \"%s\"\n", filename);
-            return 1;
-        }
-    }
-    return 0;
+int applypatch_check(const char* filename, const std::vector<std::string>& patch_sha1_str) {
+  FileContents file;
+
+  // It's okay to specify no sha1s; the check will pass if the
+  // LoadFileContents is successful.  (Useful for reading
+  // partitions, where the filename encodes the sha1s; no need to
+  // check them twice.)
+  if (LoadFileContents(filename, &file) != 0 ||
+      (!patch_sha1_str.empty() && FindMatchingPatch(file.sha1, patch_sha1_str) < 0)) {
+    printf("file \"%s\" doesn't have any of expected sha1 sums; checking cache\n", filename);
+
+    // If the source file is missing or corrupted, it might be because
+    // we were killed in the middle of patching it.  A copy of it
+    // should have been made in CACHE_TEMP_SOURCE.  If that file
+    // exists and matches the sha1 we're looking for, the check still
+    // passes.
+    if (LoadFileContents(CACHE_TEMP_SOURCE, &file) != 0) {
+      printf("failed to load cache file\n");
+      return 1;
+    }
+
+    if (FindMatchingPatch(file.sha1, patch_sha1_str) < 0) {
+      printf("cache bits don't match any sha1 for \"%s\"\n", filename);
+      return 1;
+    }
+  }
+  return 0;
 }
 
 int ShowLicenses() {
@@ -633,116 +565,97 @@ size_t FreeSpaceForFile(const char* filename) {
 
 int CacheSizeCheck(size_t bytes) {
     if (MakeFreeSpaceOnCache(bytes) < 0) {
-        printf("unable to make %ld bytes available on /cache\n", (long)bytes);
+        printf("unable to make %zu bytes available on /cache\n", bytes);
         return 1;
     } else {
         return 0;
     }
 }
 
-// This function applies binary patches to files in a way that is safe
-// (the original file is not touched until we have the desired
-// replacement for it) and idempotent (it's okay to run this program
-// multiple times).
+// This function applies binary patches to EMMC target files in a way that is safe (the original
+// file is not touched until we have the desired replacement for it) and idempotent (it's okay to
+// run this program multiple times).
 //
-// - if the sha1 hash of <target_filename> is <target_sha1_string>,
-//   does nothing and exits successfully.
+// - If the SHA-1 hash of <target_filename> is <target_sha1_string>, does nothing and exits
+//   successfully.
 //
-// - otherwise, if the sha1 hash of <source_filename> is one of the
-//   entries in <patch_sha1_str>, the corresponding patch from
-//   <patch_data> (which must be a VAL_BLOB) is applied to produce a
-//   new file (the type of patch is automatically detected from the
-//   blob data).  If that new file has sha1 hash <target_sha1_str>,
-//   moves it to replace <target_filename>, and exits successfully.
-//   Note that if <source_filename> and <target_filename> are not the
-//   same, <source_filename> is NOT deleted on success.
-//   <target_filename> may be the string "-" to mean "the same as
-//   source_filename".
+// - Otherwise, if the SHA-1 hash of <source_filename> is one of the entries in <patch_sha1_str>,
+//   the corresponding patch from <patch_data> (which must be a VAL_BLOB) is applied to produce a
+//   new file (the type of patch is automatically detected from the blob data). If that new file
+//   has SHA-1 hash <target_sha1_str>, moves it to replace <target_filename>, and exits
+//   successfully. Note that if <source_filename> and <target_filename> are not the same,
+//   <source_filename> is NOT deleted on success. <target_filename> may be the string "-" to mean
+//   "the same as <source_filename>".
 //
-// - otherwise, or if any error is encountered, exits with non-zero
-//   status.
+// - Otherwise, or if any error is encountered, exits with non-zero status.
 //
-// <source_filename> may refer to a partition to read the source data.
-// See the comments for the LoadPartitionContents() function above
-// for the format of such a filename.
-
-int applypatch(const char* source_filename,
-               const char* target_filename,
-               const char* target_sha1_str,
-               size_t target_size,
-               int num_patches,
-               char** const patch_sha1_str,
-               Value** patch_data,
-               Value* bonus_data) {
-    printf("patch %s: ", source_filename);
-
-    if (target_filename[0] == '-' && target_filename[1] == '\0') {
-        target_filename = source_filename;
-    }
-
-    uint8_t target_sha1[SHA_DIGEST_LENGTH];
-    if (ParseSha1(target_sha1_str, target_sha1) != 0) {
-        printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
-        return 1;
-    }
-
-    FileContents copy_file;
-    FileContents source_file;
-    const Value* source_patch_value = NULL;
-    const Value* copy_patch_value = NULL;
-
-    // We try to load the target file into the source_file object.
-    if (LoadFileContents(target_filename, &source_file) == 0) {
-        if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) {
-            // The early-exit case:  the patch was already applied, this file
-            // has the desired hash, nothing for us to do.
-            printf("already %s\n", short_sha1(target_sha1).c_str());
-            return 0;
-        }
-    }
-
-    if (source_file.data.empty() ||
-        (target_filename != source_filename &&
-         strcmp(target_filename, source_filename) != 0)) {
-        // Need to load the source file:  either we failed to load the
-        // target file, or we did but it's different from the source file.
-        source_file.data.clear();
-        LoadFileContents(source_filename, &source_file);
-    }
-
-    if (!source_file.data.empty()) {
-        int to_use = FindMatchingPatch(source_file.sha1, patch_sha1_str, num_patches);
-        if (to_use >= 0) {
-            source_patch_value = patch_data[to_use];
-        }
-    }
-
-    if (source_patch_value == NULL) {
-        source_file.data.clear();
-        printf("source file is bad; trying copy\n");
-
-        if (LoadFileContents(CACHE_TEMP_SOURCE, &copy_file) < 0) {
-            // fail.
-            printf("failed to read copy file\n");
-            return 1;
-        }
-
-        int to_use = FindMatchingPatch(copy_file.sha1, patch_sha1_str, num_patches);
-        if (to_use >= 0) {
-            copy_patch_value = patch_data[to_use];
-        }
-
-        if (copy_patch_value == NULL) {
-            // fail.
-            printf("copy file doesn't match source SHA-1s either\n");
-            return 1;
-        }
-    }
-
-    return GenerateTarget(&source_file, source_patch_value,
-                          &copy_file, copy_patch_value,
-                          source_filename, target_filename,
-                          target_sha1, target_size, bonus_data);
+// <source_filename> must refer to an EMMC partition to read the source data. See the comments for
+// the LoadPartitionContents() function above for the format of such a filename. <target_size> has
+// become obsolete since we have dropped the support for patching non-EMMC targets (EMMC targets
+// have the size embedded in the filename).
+int applypatch(const char* source_filename, const char* target_filename,
+               const char* target_sha1_str, size_t target_size __unused,
+               const std::vector<std::string>& patch_sha1_str,
+               const std::vector<std::unique_ptr<Value>>& patch_data, const Value* bonus_data) {
+  printf("patch %s: ", source_filename);
+
+  if (target_filename[0] == '-' && target_filename[1] == '\0') {
+    target_filename = source_filename;
+  }
+
+  if (strncmp(target_filename, "EMMC:", 5) != 0) {
+    printf("Supporting patching EMMC targets only.\n");
+    return 1;
+  }
+
+  uint8_t target_sha1[SHA_DIGEST_LENGTH];
+  if (ParseSha1(target_sha1_str, target_sha1) != 0) {
+    printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
+    return 1;
+  }
+
+  // We try to load the target file into the source_file object.
+  FileContents source_file;
+  if (LoadFileContents(target_filename, &source_file) == 0) {
+    if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) {
+      // The early-exit case: the patch was already applied, this file has the desired hash, nothing
+      // for us to do.
+      printf("already %s\n", short_sha1(target_sha1).c_str());
+      return 0;
+    }
+  }
+
+  if (source_file.data.empty() ||
+      (target_filename != source_filename && strcmp(target_filename, source_filename) != 0)) {
+    // Need to load the source file: either we failed to load the target file, or we did but it's
+    // different from the expected.
+    source_file.data.clear();
+    LoadFileContents(source_filename, &source_file);
+  }
+
+  if (!source_file.data.empty()) {
+    int to_use = FindMatchingPatch(source_file.sha1, patch_sha1_str);
+    if (to_use != -1) {
+      return GenerateTarget(source_file, patch_data[to_use], target_filename, target_sha1,
+                            bonus_data);
+    }
+  }
+
+  printf("source file is bad; trying copy\n");
+
+  FileContents copy_file;
+  if (LoadFileContents(CACHE_TEMP_SOURCE, &copy_file) < 0) {
+    printf("failed to read copy file\n");
+    return 1;
+  }
+
+  int to_use = FindMatchingPatch(copy_file.sha1, patch_sha1_str);
+  if (to_use == -1) {
+    printf("copy file doesn't match source SHA-1s either\n");
+    return 1;
+  }
+
+  return GenerateTarget(copy_file, patch_data[to_use], target_filename, target_sha1, bonus_data);
 }
 
 /*
@@ -754,281 +667,124 @@ int applypatch(const char* source_filename,
  */
 int applypatch_flash(const char* source_filename, const char* target_filename,
                      const char* target_sha1_str, size_t target_size) {
-    printf("flash %s: ", target_filename);
-
-    uint8_t target_sha1[SHA_DIGEST_LENGTH];
-    if (ParseSha1(target_sha1_str, target_sha1) != 0) {
-        printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
-        return 1;
-    }
-
-    FileContents source_file;
-    std::string target_str(target_filename);
-
-    std::vector<std::string> pieces = android::base::Split(target_str, ":");
-    if (pieces.size() != 2 || (pieces[0] != "MTD" && pieces[0] != "EMMC")) {
-        printf("invalid target name \"%s\"", target_filename);
-        return 1;
-    }
-
-    // Load the target into the source_file object to see if already applied.
-    pieces.push_back(std::to_string(target_size));
-    pieces.push_back(target_sha1_str);
-    std::string fullname = android::base::Join(pieces, ':');
-    if (LoadPartitionContents(fullname.c_str(), &source_file) == 0 &&
-        memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) {
-        // The early-exit case: the image was already applied, this partition
-        // has the desired hash, nothing for us to do.
-        printf("already %s\n", short_sha1(target_sha1).c_str());
-        return 0;
-    }
-
-    if (LoadFileContents(source_filename, &source_file) == 0) {
-        if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) {
-            // The source doesn't have desired checksum.
-            printf("source \"%s\" doesn't have expected sha1 sum\n", source_filename);
-            printf("expected: %s, found: %s\n", short_sha1(target_sha1).c_str(),
-                    short_sha1(source_file.sha1).c_str());
-            return 1;
-        }
-    }
-
-    if (WriteToPartition(source_file.data.data(), target_size, target_filename) != 0) {
-        printf("write of copied data to %s failed\n", target_filename);
-        return 1;
-    }
+  printf("flash %s: ", target_filename);
+
+  uint8_t target_sha1[SHA_DIGEST_LENGTH];
+  if (ParseSha1(target_sha1_str, target_sha1) != 0) {
+    printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
+    return 1;
+  }
+
+  std::string target_str(target_filename);
+  std::vector<std::string> pieces = android::base::Split(target_str, ":");
+  if (pieces.size() != 2 || pieces[0] != "EMMC") {
+    printf("invalid target name \"%s\"", target_filename);
+    return 1;
+  }
+
+  // Load the target into the source_file object to see if already applied.
+  pieces.push_back(std::to_string(target_size));
+  pieces.push_back(target_sha1_str);
+  std::string fullname = android::base::Join(pieces, ':');
+  FileContents source_file;
+  if (LoadPartitionContents(fullname, &source_file) == 0 &&
+      memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) {
+    // The early-exit case: the image was already applied, this partition
+    // has the desired hash, nothing for us to do.
+    printf("already %s\n", short_sha1(target_sha1).c_str());
     return 0;
+  }
+
+  if (LoadFileContents(source_filename, &source_file) == 0) {
+    if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) {
+      // The source doesn't have desired checksum.
+      printf("source \"%s\" doesn't have expected sha1 sum\n", source_filename);
+      printf("expected: %s, found: %s\n", short_sha1(target_sha1).c_str(),
+             short_sha1(source_file.sha1).c_str());
+      return 1;
+    }
+  }
+
+  if (WriteToPartition(source_file.data.data(), target_size, target_filename) != 0) {
+    printf("write of copied data to %s failed\n", target_filename);
+    return 1;
+  }
+  return 0;
 }
 
-static int GenerateTarget(FileContents* source_file,
-                          const Value* source_patch_value,
-                          FileContents* copy_file,
-                          const Value* copy_patch_value,
-                          const char* source_filename,
-                          const char* target_filename,
-                          const uint8_t target_sha1[SHA_DIGEST_LENGTH],
-                          size_t target_size,
-                          const Value* bonus_data) {
-    int retry = 1;
-    SHA_CTX ctx;
-    std::string memory_sink_str;
-    FileContents* source_to_use;
-    int made_copy = 0;
-
-    bool target_is_partition = (strncmp(target_filename, "MTD:", 4) == 0 ||
-                                strncmp(target_filename, "EMMC:", 5) == 0 ||
-                                strncmp(target_filename, "BML:", 4) == 0);
-    const std::string tmp_target_filename = std::string(target_filename) + ".patch";
-
-    // assume that target_filename (eg "/system/app/Foo.apk") is located
-    // on the same filesystem as its top-level directory ("/system").
-    // We need something that exists for calling statfs().
-    std::string target_fs = target_filename;
-    auto slash_pos = target_fs.find('/', 1);
-    if (slash_pos != std::string::npos) {
-        target_fs.resize(slash_pos);
-    }
-
-    const Value* patch;
-    if (source_patch_value != NULL) {
-        source_to_use = source_file;
-        patch = source_patch_value;
-    } else {
-        source_to_use = copy_file;
-        patch = copy_patch_value;
-    }
-    if (patch->type != VAL_BLOB) {
-        printf("patch is not a blob\n");
-        return 1;
-    }
-    char* header = patch->data;
-    ssize_t header_bytes_read = patch->size;
-    bool use_bsdiff = false;
-    if (header_bytes_read >= 8 && memcmp(header, "BSDIFF40", 8) == 0) {
-        use_bsdiff = true;
-    } else if (header_bytes_read >= 8 && memcmp(header, "IMGDIFF2", 8) == 0) {
-        use_bsdiff = false;
-    } else {
-        printf("Unknown patch file format\n");
-        return 1;
-    }
-
-    do {
-        // Is there enough room in the target filesystem to hold the patched
-        // file?
-
-        if (target_is_partition) {
-            // If the target is a partition, we're actually going to
-            // write the output to /tmp and then copy it to the
-            // partition.  statfs() always returns 0 blocks free for
-            // /tmp, so instead we'll just assume that /tmp has enough
-            // space to hold the file.
-
-            // We still write the original source to cache, in case
-            // the partition write is interrupted.
-            if (MakeFreeSpaceOnCache(source_file->data.size()) < 0) {
-                printf("not enough free space on /cache\n");
-                return 1;
-            }
-            if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
-                printf("failed to back up source file\n");
-                return 1;
-            }
-            made_copy = 1;
-            retry = 0;
-        } else {
-            int enough_space = 0;
-            if (retry > 0) {
-                size_t free_space = FreeSpaceForFile(target_fs.c_str());
-                enough_space =
-                    (free_space > (256 << 10)) &&          // 256k (two-block) minimum
-                    (free_space > (target_size * 3 / 2));  // 50% margin of error
-                if (!enough_space) {
-                    printf("target %zu bytes; free space %zu bytes; retry %d; enough %d\n",
-                           target_size, free_space, retry, enough_space);
-                }
-            }
-
-            if (!enough_space) {
-                retry = 0;
-            }
-
-            if (!enough_space && source_patch_value != NULL) {
-                // Using the original source, but not enough free space.  First
-                // copy the source file to cache, then delete it from the original
-                // location.
-
-                if (strncmp(source_filename, "MTD:", 4) == 0 ||
-                    strncmp(source_filename, "EMMC:", 5) == 0 ||
-                    strncmp(source_filename, "BML:", 4) == 0) {
-                    // It's impossible to free space on the target filesystem by
-                    // deleting the source if the source is a partition.  If
-                    // we're ever in a state where we need to do this, fail.
-                    printf("not enough free space for target but source is partition\n");
-                    return 1;
-                }
-
-                if (MakeFreeSpaceOnCache(source_file->data.size()) < 0) {
-                    printf("not enough free space on /cache\n");
-                    return 1;
-                }
-
-                if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
-                    printf("failed to back up source file\n");
-                    return 1;
-                }
-                made_copy = 1;
-                unlink(source_filename);
-
-                size_t free_space = FreeSpaceForFile(target_fs.c_str());
-                printf("(now %zu bytes free for target) ", free_space);
-            }
-        }
-
-
-        SinkFn sink = NULL;
-        void* token = NULL;
-
-        int output_fd = -1;
-        if (target_is_partition) {
-            // We store the decoded output in memory.
-            sink = MemorySink;
-            token = &memory_sink_str;
-        } else {
-            // We write the decoded output to "<tgt-file>.patch".
-            output_fd = ota_open(tmp_target_filename.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_SYNC,
-                          S_IRUSR | S_IWUSR);
-            if (output_fd < 0) {
-                printf("failed to open output file %s: %s\n", tmp_target_filename.c_str(),
-                       strerror(errno));
-                return 1;
-            }
-            sink = FileSink;
-            token = &output_fd;
-        }
-
-
-        SHA1_Init(&ctx);
-
-        int result;
-        if (use_bsdiff) {
-            result = ApplyBSDiffPatch(source_to_use->data.data(), source_to_use->data.size(),
-                                      patch, 0, sink, token, &ctx);
-        } else {
-            result = ApplyImagePatch(source_to_use->data.data(), source_to_use->data.size(),
-                                     patch, sink, token, &ctx, bonus_data);
-        }
-
-        if (!target_is_partition) {
-            if (ota_fsync(output_fd) != 0) {
-                printf("failed to fsync file \"%s\" (%s)\n", tmp_target_filename.c_str(),
-                       strerror(errno));
-                result = 1;
-            }
-            if (ota_close(output_fd) != 0) {
-                printf("failed to close file \"%s\" (%s)\n", tmp_target_filename.c_str(),
-                       strerror(errno));
-                result = 1;
-            }
-        }
-
-        if (result != 0) {
-            if (retry == 0) {
-                printf("applying patch failed\n");
-                return result != 0;
-            } else {
-                printf("applying patch failed; retrying\n");
-            }
-            if (!target_is_partition) {
-                unlink(tmp_target_filename.c_str());
-            }
-        } else {
-            // succeeded; no need to retry
-            break;
-        }
-    } while (retry-- > 0);
-
-    uint8_t current_target_sha1[SHA_DIGEST_LENGTH];
-    SHA1_Final(current_target_sha1, &ctx);
-    if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) {
-        printf("patch did not produce expected sha1\n");
-        return 1;
-    } else {
-        printf("now %s\n", short_sha1(target_sha1).c_str());
-    }
-
-    if (target_is_partition) {
-        // Copy the temp file to the partition.
-        if (WriteToPartition(reinterpret_cast<const unsigned char*>(memory_sink_str.c_str()),
-                             memory_sink_str.size(), target_filename) != 0) {
-            printf("write of patched data to %s failed\n", target_filename);
-            return 1;
-        }
-    } else {
-        // Give the .patch file the same owner, group, and mode of the
-        // original source file.
-        if (chmod(tmp_target_filename.c_str(), source_to_use->st.st_mode) != 0) {
-            printf("chmod of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno));
-            return 1;
-        }
-        if (chown(tmp_target_filename.c_str(), source_to_use->st.st_uid, source_to_use->st.st_gid) != 0) {
-            printf("chown of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno));
-            return 1;
-        }
-
-        // Finally, rename the .patch file to replace the target file.
-        if (rename(tmp_target_filename.c_str(), target_filename) != 0) {
-            printf("rename of .patch to \"%s\" failed: %s\n", target_filename, strerror(errno));
-            return 1;
-        }
-    }
-
-    // If this run of applypatch created the copy, and we're here, we
-    // can delete it.
-    if (made_copy) {
-        unlink(CACHE_TEMP_SOURCE);
-    }
-
-    // Success!
-    return 0;
+static int GenerateTarget(const FileContents& source_file, const std::unique_ptr<Value>& patch,
+                          const std::string& target_filename,
+                          const uint8_t target_sha1[SHA_DIGEST_LENGTH], const Value* bonus_data) {
+  if (patch->type != VAL_BLOB) {
+    printf("patch is not a blob\n");
+    return 1;
+  }
+
+  const char* header = &patch->data[0];
+  size_t header_bytes_read = patch->data.size();
+  bool use_bsdiff = false;
+  if (header_bytes_read >= 8 && memcmp(header, "BSDIFF40", 8) == 0) {
+    use_bsdiff = true;
+  } else if (header_bytes_read >= 8 && memcmp(header, "IMGDIFF2", 8) == 0) {
+    use_bsdiff = false;
+  } else {
+    printf("Unknown patch file format\n");
+    return 1;
+  }
+
+  CHECK(android::base::StartsWith(target_filename, "EMMC:"));
+
+  // We still write the original source to cache, in case the partition write is interrupted.
+  if (MakeFreeSpaceOnCache(source_file.data.size()) < 0) {
+    printf("not enough free space on /cache\n");
+    return 1;
+  }
+  if (SaveFileContents(CACHE_TEMP_SOURCE, &source_file) < 0) {
+    printf("failed to back up source file\n");
+    return 1;
+  }
+
+  // We store the decoded output in memory.
+  SinkFn sink = MemorySink;
+  std::string memory_sink_str;  // Don't need to reserve space.
+  void* token = &memory_sink_str;
+
+  SHA_CTX ctx;
+  SHA1_Init(&ctx);
+
+  int result;
+  if (use_bsdiff) {
+    result = ApplyBSDiffPatch(source_file.data.data(), source_file.data.size(), patch.get(), 0,
+                              sink, token, &ctx);
+  } else {
+    result = ApplyImagePatch(source_file.data.data(), source_file.data.size(), patch.get(), sink,
+                             token, &ctx, bonus_data);
+  }
+
+  if (result != 0) {
+    printf("applying patch failed\n");
+    return 1;
+  }
+
+  uint8_t current_target_sha1[SHA_DIGEST_LENGTH];
+  SHA1_Final(current_target_sha1, &ctx);
+  if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_LENGTH) != 0) {
+    printf("patch did not produce expected sha1\n");
+    return 1;
+  } else {
+    printf("now %s\n", short_sha1(target_sha1).c_str());
+  }
+
+  // Write back the temp file to the partition.
+  if (WriteToPartition(reinterpret_cast<const unsigned char*>(memory_sink_str.c_str()),
+                       memory_sink_str.size(), target_filename) != 0) {
+    printf("write of patched data to %s failed\n", target_filename.c_str());
+    return 1;
+  }
+
+  // Delete the backup copy of the source.
+  unlink(CACHE_TEMP_SOURCE);
+
+  // Success!
+  return 0;
 }