commit 55405b61be6d0c272060cc4fed42693340fd9135
author Kalesh Singh <kaleshsingh@google.com> Thu Aug 17 09:44:45 2023 -0700
committer Kalesh Singh <kaleshsingh@google.com> Thu Aug 24 14:46:13 2023 -0700
tree 40e7463381e6edb56a290245933986ee34b0877a
parent 7e0aa04637c0f502915dd7cf8c03d29cfd21fc6c

zipalign: Allow specifiying the target page size

Allow apps to specify the target page size for aligning their
uncompressed shared libraries.

This allows apps that want to support larger page sizes to do
so by specifiying the -P <pagesize_kb> flag.

However, apps built for 4k-only devices are unaffected as they
can continue to use -p flag for 4kB page alignment of uncompressed
shared libraries.

Bug: 276963821
Test: atest -c zipalign_tests
Change-Id: I890db067b8f898045f73e86788662f94a48af772
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>

tools/zipalign/ZipAlign.cpp

diff --git a/tools/zipalign/ZipAlign.cpp b/tools/zipalign/ZipAlign.cpp
index 23840e3..f32f90b 100644
--- a/tools/zipalign/ZipAlign.cpp
+++ b/tools/zipalign/ZipAlign.cpp
@@ -17,6 +17,7 @@
 #include "ZipFile.h"
 
 #include <stdio.h>
+#include <string.h>
 #include <stdlib.h>
 #include <unistd.h>
 
@@ -36,17 +37,14 @@
 }
 
 static int getAlignment(bool pageAlignSharedLibs, int defaultAlignment,
-    ZipEntry* pEntry) {
-
-    static const int kPageAlignment = 4096;
-
+    ZipEntry* pEntry, int pageSize) {
     if (!pageAlignSharedLibs) {
         return defaultAlignment;
     }
 
     const char* ext = strrchr(pEntry->getFileName(), '.');
     if (ext && strcmp(ext, ".so") == 0) {
-        return kPageAlignment;
+        return pageSize;
     }
 
     return defaultAlignment;
@@ -56,7 +54,7 @@
  * Copy all entries from "pZin" to "pZout", aligning as needed.
  */
 static int copyAndAlign(ZipFile* pZin, ZipFile* pZout, int alignment, bool zopfli,
-    bool pageAlignSharedLibs)
+    bool pageAlignSharedLibs, int pageSize)
 {
     int numEntries = pZin->getNumEntries();
     ZipEntry* pEntry;
@@ -84,7 +82,8 @@
                 status = pZout->add(pZin, pEntry, padding, &pNewEntry);
             }
         } else {
-            const int alignTo = getAlignment(pageAlignSharedLibs, alignment, pEntry);
+            const int alignTo = getAlignment(pageAlignSharedLibs, alignment, pEntry,
+                                             pageSize);
 
             //printf("--- %s: orig at %ld(+%d) len=%ld, adding pad=%d\n",
             //    pEntry->getFileName(), (long) pEntry->getFileOffset(),
@@ -107,7 +106,7 @@
  * output file exists and "force" wasn't specified.
  */
 int process(const char* inFileName, const char* outFileName,
-    int alignment, bool force, bool zopfli, bool pageAlignSharedLibs)
+    int alignment, bool force, bool zopfli, bool pageAlignSharedLibs, int pageSize)
 {
     ZipFile zin, zout;
 
@@ -127,7 +126,7 @@
     }
 
     if (zin.open(inFileName, ZipFile::kOpenReadOnly) != OK) {
-        fprintf(stderr, "Unable to open '%s' as zip archive\n", inFileName);
+        fprintf(stderr, "Unable to open '%s' as zip archive: %s\n", inFileName, strerror(errno));
         return 1;
     }
     if (zout.open(outFileName,
@@ -138,7 +137,8 @@
         return 1;
     }
 
-    int result = copyAndAlign(&zin, &zout, alignment, zopfli, pageAlignSharedLibs);
+    int result = copyAndAlign(&zin, &zout, alignment, zopfli, pageAlignSharedLibs,
+                              pageSize);
     if (result != 0) {
         printf("zipalign: failed rewriting '%s' to '%s'\n",
             inFileName, outFileName);
@@ -150,7 +150,7 @@
  * Verify the alignment of a zip archive.
  */
 int verify(const char* fileName, int alignment, bool verbose,
-    bool pageAlignSharedLibs)
+    bool pageAlignSharedLibs, int pageSize)
 {
     ZipFile zipFile;
     bool foundBad = false;
@@ -181,7 +181,8 @@
             continue;
        } else {
             off_t offset = pEntry->getFileOffset();
-            const int alignTo = getAlignment(pageAlignSharedLibs, alignment, pEntry);
+            const int alignTo = getAlignment(pageAlignSharedLibs, alignment, pEntry,
+                                             pageSize);
             if ((offset % alignTo) != 0) {
                 if (verbose) {
                     printf("%8jd %s (BAD - %jd)\n",