Issue 153 NEW PR (#167)

* issue153

* fix issue 153

* malloc->calloc

* add zip_open_stream() to readme

Co-authored-by: hanjinfei57 <hanjinfei57@gmail.com>

README.md

@@ -154,6 +154,38 @@ struct zip_t *zip = zip_open("foo.zip", 0, 'r');
 zip_close(zip);
 ```
 
+* Create a new zip archive in memory.
+
+```c
+char *buf_encode = NULL;
+const char *buf = "Append some data here...\0";
+struct zip_t *zip = zip_open_stream(NULL, 0, ZIP_DEFAULT_COMPRESSION_LEVEL, 'w');
+{
+    zip_entry_open(zip, "foo-1.txt");
+  	zip_entry_write(zip, buf, strlen(buf));
+  	zip_entry_close(zip);
+  	/* copy compressed mem to buf_encode */
+  	size_t n = zip_copy_stream(zip, (void **)&buf_encode, NULL);
+}
+zip_close_stream(zip);
+free(buf_encode);
+```
+
+* Extract a zip entry into a memory.
+
+```c
+char *buf = NULL;
+struct zip_t *zipStream = zip_open_stream(buf_encode, n, 0, 'r');
+{
+    zip_entry_open(zipStream, "foo-1.txt");
+  	ssize_t bufsize;
+  	bufsize = zip_entry_read(zipStream, (void **)&buf, NULL);
+    zip_entry_close(zipStream);
+}
+zip_close_stream(zipStream);
+free(buf);
+```
+
 * List of all zip entries
 ```c
 struct zip_t *zip = zip_open("foo.zip", 0, 'r');

src/zip.c

@@ -72,7 +72,9 @@
 static int file_truncate(mz_zip_archive *pZip) {
   mz_zip_internal_state *pState = pZip->m_pState;
   mz_uint64 file_size = pZip->m_archive_size;
-
+  if ((pZip->m_pWrite == mz_zip_heap_write_func) && (pState->m_pMem)) {
+    return 0;
+  }
   if (pZip->m_zip_mode == MZ_ZIP_MODE_WRITING_HAS_BEEN_FINALIZED) {
     if (pState->m_pFile) {
       int fd = fileno(pState->m_pFile);
@@ -1076,13 +1078,30 @@ struct entry_mark {
   mz_uint64 lf_length;
 };
 
-struct zip_t *zip_open_stream(const char *stream, size_t size) {
+struct zip_t *zip_open_stream(const char *stream, size_t size, int level, char mode) {
   struct zip_t *zip = NULL;
   zip = (struct zip_t *)calloc((size_t)1, sizeof(struct zip_t));
   if (!zip) {
     return NULL;
   }
-  if (!mz_zip_reader_init_mem(&(zip->archive), stream, size, 0)) {
+  if (level < 0)
+    level = MZ_DEFAULT_LEVEL;
+  if ((level & 0xF) > MZ_UBER_COMPRESSION) {
+    // Wrong compression level
+    goto cleanup;
+  }
+  zip->level = (mz_uint)level;
+  if((stream != NULL) && (size > 0) && (mode == 'r')){
+    if (!mz_zip_reader_init_mem(&(zip->archive), stream, size, 0)) {
+      goto cleanup;
+    }
+  }else if((stream == NULL) && (size == 0) && (mode == 'w')){
+    // Create a new archive.
+    if (!mz_zip_writer_init_heap(&(zip->archive), 0, 1024)) {
+      // Cannot initialize zip_archive writer
+      goto cleanup;
+    }
+  }else{
     goto cleanup;
   }
   return zip;
@@ -1092,6 +1111,31 @@ cleanup:
   return NULL;
 }
 
+static inline void zip_write_end(struct zip_t *zip){
+    if (zip) {
+    mz_zip_writer_finalize_archive(&(zip->archive));
+    file_truncate(&(zip->archive));
+  }
+}
+
+ssize_t zip_copy_stream(struct zip_t *zip, void **buf, ssize_t *bufsize){
+  if(zip == NULL) return -1;
+  zip_write_end(zip);
+  if(bufsize != NULL)
+    *bufsize = zip->archive.m_archive_size;
+  *buf = (char *)calloc(sizeof(unsigned char), zip->archive.m_archive_size);
+  memcpy(*buf, zip->archive.m_pState->m_pMem, zip->archive.m_archive_size);
+  return zip->archive.m_archive_size;
+}
+
+void zip_close_stream(struct zip_t *zip){
+  if (zip) {
+    mz_zip_writer_end(&(zip->archive));
+    mz_zip_reader_end(&(zip->archive));
+    CLEANUP(zip);
+  }
+}
+
 static mz_bool file_name_matches(const char *file_name,
                                  const char *delete_name) {
   int delete_name_length = strlen(delete_name);

src/zip.h

@@ -331,7 +331,28 @@ extern int zip_extract_stream(const char *stream, size_t size, const char *dir,
  *
  * @return the zip archive handler or NULL on error
  */
-extern struct zip_t *zip_open_stream(const char *stream, size_t size);
+extern struct zip_t *zip_open_stream(const char *stream, size_t size,
+                                     int level, char mode);
+
+/**
+ * Copy zip archive stream output buffer.
+ *
+ * @param zip zip archive handler.
+ * @param buf output buffer. User should free buf.
+ * @param bufsize output buffer size (in bytes).
+ *
+ * @return copy size
+ */
+extern ssize_t zip_copy_stream(struct zip_t *zip, void **buf, ssize_t *bufsize);
+
+/**
+ * Close zip archive releases resources.
+ *
+ * @param zip zip archive handler.
+ *
+ * @return
+ */
+extern void zip_close_stream(struct zip_t *zip);
 
 /**
  * Deletes zip archive entries.

test/test.c

@@ -547,32 +547,20 @@ static void test_open_stream(void) {
 #if defined(_WIN64) || defined(_WIN32) || defined(__WIN32__)
 #else
   remove(ZIPNAME);
-
-  struct zip_t *zip = zip_open(ZIPNAME, ZIP_DEFAULT_COMPRESSION_LEVEL, 'w');
+  /* COMPRESS MEM TO MEM */
+  struct zip_t *zip = zip_open_stream(NULL, 0, ZIP_DEFAULT_COMPRESSION_LEVEL, 'w');
   assert(zip != NULL);
 
   assert(0 == zip_entry_open(zip, "test/test-1.txt"));
   assert(0 == zip_entry_write(zip, TESTDATA1, strlen(TESTDATA1)));
   assert(0 == zip_entry_close(zip));
 
-  zip_close(zip);
-
-  FILE *fp = NULL;
-  fp = fopen(ZIPNAME, "r");
-  assert(fp != NULL);
-
-  fseek(fp, 0L, SEEK_END);
-  size_t filesize = ftell(fp);
-  fseek(fp, 0L, SEEK_SET);
-
-  char stream[filesize];
-  memset(stream, 0, filesize);
-  size_t size = fread(stream, sizeof(char), filesize, fp);
-  assert(filesize == size);
-
-  fclose(fp);
-
-  struct zip_t *zipStream = zip_open_stream(stream, size);
+  /* write compressed mem to file */
+  char *buf_encode = NULL;
+  size_t n = zip_copy_stream(zip, (void **)&buf_encode, NULL);
+  zip_close_stream(zip);
+  /* DECOMPRESS MEM TO MEM */
+  struct zip_t *zipStream = zip_open_stream(buf_encode, n, 0, 'r');
   assert(zipStream != NULL);
 
   assert(0 == zip_entry_open(zipStream, "test/test-1.txt"));
@@ -582,9 +570,10 @@ static void test_open_stream(void) {
   bufsize = zip_entry_read(zipStream, (void **)&buf, NULL);
   assert(0 == strncmp(buf, TESTDATA1, (size_t)bufsize));
   assert(0 == zip_entry_close(zipStream));
+  zip_close_stream(zipStream);
 
   free(buf);
-  zip_close(zipStream);
+  free(buf_encode);
   remove(ZIPNAME);
 #endif
 }