add mzGetStoredEntry function

mzGetStoredEntry gives you a pointer and address to the data of a zip
entry, assuming that entry is stored rather than deflated.

Change-Id: Ifb39777c98d1d50475ef7de419cf28935f5f9965

2 files changed, 30 insertions, 2 deletions

diff --git a/minzip/Zip.c b/minzip/Zip.c
index 6785d4e..abc9890 100644
--- a/minzip/Zip.c
+++ b/minzip/Zip.c
@@ -703,7 +703,7 @@ static bool writeProcessFunction(const unsigned char *data, int dataLen,
     while (true) {
         ssize_t n = write(fd, data+soFar, dataLen-soFar);
         if (n <= 0) {
-            LOGE("Error writing %ld bytes from zip file from %p: %s\n",
+            LOGE("Error writing %zd bytes from zip file from %p: %s\n",
                  dataLen-soFar, data+soFar, strerror(errno));
             if (errno != EINTR) {
               return false;
@@ -712,7 +712,7 @@ static bool writeProcessFunction(const unsigned char *data, int dataLen,
             soFar += n;
             if (soFar == dataLen) return true;
             if (soFar > dataLen) {
-                LOGE("write overrun?  (%ld bytes instead of %d)\n",
+                LOGE("write overrun?  (%zd bytes instead of %d)\n",
                      soFar, dataLen);
                 return false;
             }
@@ -735,6 +735,23 @@ bool mzExtractZipEntryToFile(const ZipArchive *pArchive,
     return true;
 }
 
+/*
+ * Obtain a pointer to the in-memory representation of a stored entry.
+ */
+bool mzGetStoredEntry(const ZipArchive *pArchive,
+    const ZipEntry *pEntry, unsigned char **addr, size_t *length)
+{
+    if (pEntry->compression != STORED) {
+        LOGE("Can't getStoredEntry for '%s'; not stored\n",
+             pEntry->fileName);
+        return false;
+    }
+
+    *addr = pArchive->addr + pEntry->offset;
+    *length = pEntry->uncompLen;
+    return true;
+}
+
 typedef struct {
     unsigned char* buffer;
     long len;
diff --git a/minzip/Zip.h b/minzip/Zip.h
index 05a2e60..2054b38 100644
--- a/minzip/Zip.h
+++ b/minzip/Zip.h
@@ -183,6 +183,17 @@ bool mzExtractZipEntryToBuffer(const ZipArchive *pArchive,
     const ZipEntry *pEntry, unsigned char* buffer);
 
 /*
+ * Return a pointer and length for a given entry.  The returned region
+ * should be valid until pArchive is closed, and should be treated as
+ * read-only.
+ *
+ * Only makes sense for entries which are stored (ie, not compressed).
+ * No guarantees are made regarding alignment of the returned pointer.
+ */
+bool mzGetStoredEntry(const ZipArchive *pArchive,
+    const ZipEntry* pEntry, unsigned char **addr, size_t *length);
+
+/*
  * Inflate all entries under zipDir to the directory specified by
  * targetDir, which must exist and be a writable directory.
  *