applypatch: Consolidate CacheSizeCheck() and MakeFreeSpaceOnCache().

They are doing exactly the same thing, except for the slightly different
error return value (1 vs -1).

int CacheSizeCheck(size_t bytes);
int MakeFreeSpaceOnCache(size_t bytes_needed);

This CL consolidates the two functions and uses bool as its return type.

// Checks whether /cache partition has at least 'bytes'-byte free space. Returns true immediately
// if so. Otherwise, it will try to free some space by removing older logs, checks again and
// returns the checking result.
bool CheckAndFreeSpaceOnCache(size_t bytes);

Test: Run recovery_unit_test and recovery_component_test on marlin.
Change-Id: I94a96934d2b18713f8f39ad5aa96a02c98d87963

3 files changed, 12 insertions, 21 deletions

diff --git a/applypatch/applypatch.cpp b/applypatch/applypatch.cpp
index 13e4b1ae..12e13993 100644
--- a/applypatch/applypatch.cpp
+++ b/applypatch/applypatch.cpp
@@ -420,14 +420,6 @@ static size_t FileSink(const unsigned char* data, size_t len, int fd) {
   return done;
 }
 
-int CacheSizeCheck(size_t bytes) {
-  if (MakeFreeSpaceOnCache(bytes) < 0) {
-    LOG(ERROR) << "Failed to make " << bytes << " bytes available on /cache";
-    return 1;
-  }
-  return 0;
-}
-
 int applypatch(const char* source_filename, const char* target_filename,
                const char* target_sha1_str, size_t /* target_size */,
                const std::vector<std::string>& patch_sha1s,
@@ -562,8 +554,8 @@ static int GenerateTarget(const FileContents& source_file, const std::unique_ptr
 
   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) {
+  // We write the original source to cache, in case the partition write is interrupted.
+  if (!CheckAndFreeSpaceOnCache(source_file.data.size())) {
     LOG(ERROR) << "Not enough free space on /cache";
     return 1;
   }
diff --git a/applypatch/freecache.cpp b/applypatch/freecache.cpp
index 4989b749..e4878655 100644
--- a/applypatch/freecache.cpp
+++ b/applypatch/freecache.cpp
@@ -150,22 +150,22 @@ static int64_t FreeSpaceForFile(const std::string& filename) {
   return free_space;
 }
 
-int MakeFreeSpaceOnCache(size_t bytes_needed) {
+bool CheckAndFreeSpaceOnCache(size_t bytes) {
 #ifndef __ANDROID__
   // TODO(xunchang): Implement a heuristic cache size check during host simulation.
-  LOG(WARNING) << "Skipped making (" << bytes_needed
+  LOG(WARNING) << "Skipped making (" << bytes
                << ") bytes free space on /cache; program is running on host";
-  return 0;
+  return true;
 #endif
 
   std::vector<std::string> dirs{ "/cache", Paths::Get().cache_log_directory() };
   for (const auto& dirname : dirs) {
-    if (RemoveFilesInDirectory(bytes_needed, dirname, FreeSpaceForFile)) {
-      return 0;
+    if (RemoveFilesInDirectory(bytes, dirname, FreeSpaceForFile)) {
+      return true;
     }
   }
 
-  return -1;
+  return false;
 }
 
 bool RemoveFilesInDirectory(size_t bytes_needed, const std::string& dirname,
diff --git a/applypatch/include/applypatch/applypatch.h b/applypatch/include/applypatch/applypatch.h
index 88659b86..28dba7e6 100644
--- a/applypatch/include/applypatch/applypatch.h
+++ b/applypatch/include/applypatch/applypatch.h
@@ -40,10 +40,6 @@ using SinkFn = std::function<size_t(const unsigned char*, size_t)>;
 
 int ShowLicenses();
 
-// Checks whether /cache partition has at least 'bytes'-byte free space. Returns 0 on having
-// sufficient space.
-int CacheSizeCheck(size_t bytes);
-
 // Parses a given string of 40 hex digits into 20-byte array 'digest'. 'str' may contain only the
 // digest or be of the form "<digest>:<anything>". Returns 0 on success, or -1 on any error.
 int ParseSha1(const std::string& str, uint8_t* digest);
@@ -113,7 +109,10 @@ int ApplyImagePatch(const unsigned char* old_data, size_t old_size, const Value&
 
 // freecache.cpp
 
-int MakeFreeSpaceOnCache(size_t bytes_needed);
+// Checks whether /cache partition has at least 'bytes'-byte free space. Returns true immediately
+// if so. Otherwise, it will try to free some space by removing older logs, checks again and
+// returns the checking result.
+bool CheckAndFreeSpaceOnCache(size_t bytes);
 
 // Removes the files in |dirname| until we have at least |bytes_needed| bytes of free space on the
 // partition. |space_checker| should return the size of the free space, or -1 on error.