Add Untar_FromChunk_Print() + Test

2 files changed, 197 insertions, 1 deletions

diff --git a/cpukit/libmisc/untar/untar.c b/cpukit/libmisc/untar/untar.c
index f6f4f0c837..9a14f67e4e 100644
--- a/cpukit/libmisc/untar/untar.c
+++ b/cpukit/libmisc/untar/untar.c
@@ -37,7 +37,6 @@
 #include <rtems/untar.h>
 #include <rtems/bspIo.h>
 
-
 /*
  * TAR file format:
 
@@ -541,6 +540,110 @@ Untar_FromFile_Print(
   return retval;
 }
 
+
+void Untar_ChunkContext_Init(Untar_ChunkContext *context)
+{
+  context->state = UNTAR_CHUNK_HEADER;
+  context->done_bytes = 0;
+  context->out_fd = -1;
+}
+
+int Untar_FromChunk_Print(
+  Untar_ChunkContext *context,
+  void *chunk,
+  size_t chunk_size,
+  const rtems_printer* printer
+)
+{
+  char *buf;
+  size_t done;
+  size_t todo;
+  size_t remaining;
+  size_t consume;
+  int retval;
+  unsigned char linkflag;
+
+  buf = chunk;
+  done = 0;
+  todo = chunk_size;
+
+  while (todo > 0) {
+    switch (context->state) {
+      case UNTAR_CHUNK_HEADER:
+        remaining = 512 - context->done_bytes;
+        consume = MIN(remaining, todo);
+        memcpy(&context->header[context->done_bytes], &buf[done], consume);
+        context->done_bytes += consume;
+
+        if (context->done_bytes == 512) {
+          retval = Untar_ProcessHeader(
+            &context->header[0],
+            &context->fname[0],
+            &context->todo_bytes,
+            &context->todo_blocks,
+            &linkflag,
+            printer
+          );
+
+          if (retval != UNTAR_SUCCESSFUL) {
+            context->state = UNTAR_CHUNK_ERROR;
+            return retval;
+          }
+
+          if (linkflag == REGTYPE) {
+            context->out_fd = creat(&context->fname[0], 0644);
+
+            if (context->out_fd >= 0) {
+              context->state = UNTAR_CHUNK_WRITE;
+              context->done_bytes = 0;
+            } else {
+              context->state = UNTAR_CHUNK_SKIP;
+              context->todo_bytes = 512 * context->todo_blocks;
+              context->done_bytes = 0;
+            }
+          } else {
+              context->done_bytes = 0;
+          }
+        }
+
+        break;
+      case UNTAR_CHUNK_SKIP:
+        remaining = context->todo_bytes - context->done_bytes;
+        consume = MIN(remaining, todo);
+        context->done_bytes += consume;
+
+        if (context->done_bytes == context->todo_bytes) {
+          context->state = UNTAR_CHUNK_HEADER;
+          context->done_bytes = 0;
+        }
+
+        break;
+      case UNTAR_CHUNK_WRITE:
+        remaining = context->todo_bytes - context->done_bytes;
+        consume = MIN(remaining, todo);
+        write(context->out_fd, &buf[done], consume);
+        context->done_bytes += consume;
+
+        if (context->done_bytes == context->todo_bytes) {
+          close(context->out_fd);
+          context->out_fd = -1;
+          context->state = UNTAR_CHUNK_SKIP;
+          context->todo_bytes = 512 * context->todo_blocks - context->todo_bytes;
+          context->done_bytes = 0;
+        }
+
+        break;
+      default:
+        return UNTAR_FAIL;
+    }
+
+    done += consume;
+    todo -= consume;
+  }
+
+  return UNTAR_SUCCESSFUL;
+}
+
 /*
  * Function: Untar_FromFile
  *
diff --git a/cpukit/libmisc/untar/untar.h b/cpukit/libmisc/untar/untar.h
index d67c29e7f4..006f06d065 100644
--- a/cpukit/libmisc/untar/untar.h
+++ b/cpukit/libmisc/untar/untar.h
@@ -44,6 +44,99 @@ int Untar_FromMemory_Print(void *tar_buf, size_t size, const rtems_printer* prin
 int Untar_FromFile(const char *tar_name);
 int Untar_FromFile_Print(const char *tar_name, const rtems_printer* printer);
 
+typedef struct {
+  /**
+   * @brief Current context state.
+   */
+  enum {
+    UNTAR_CHUNK_HEADER,
+    UNTAR_CHUNK_SKIP,
+    UNTAR_CHUNK_WRITE,
+    UNTAR_CHUNK_ERROR
+  } state;
+
+  /**
+   * @brief Header buffer.
+   */
+  char header[512];
+
+  /**
+   * @brief Name buffer.
+   */
+  char fname[100];
+
+  /**
+   * @brief Number of bytes of overall length are already processed.
+   */
+  size_t done_bytes;
+
+  /**
+   * @brief Overall amount of bytes to be processed.
+   */
+  long unsigned todo_bytes;
+
+  /**
+   * @brief Overall amount of blocks to be processed.
+   */
+  unsigned long todo_blocks;
+
+  /**
+   * @brief File descriptor of output file.
+   */
+  int out_fd;
+} Untar_ChunkContext;
+
+typedef struct {
+  /**
+   * @brief Instance of Chunk Context needed for tar decompression.
+   */
+  Untar_ChunkContext base;
+
+  /**
+   * @brief Current zlib context.
+   */
+  z_stream strm;
+
+  /**
+   * @brief Buffer that contains the inflated data.
+   */
+  void *inflateBuffer;
+
+  /**
+   * @brief Size of buffer that contains the inflated data.
+   */
+  size_t inflateBufferSize;
+
+} Untar_GzChunkContext;
+
+/**
+ * @brief Initializes the Untar_ChunkContext files out of a part of a block of
+ * memory.
+ *
+ * @param Untar_ChunkContext *context [in] Pointer to a context structure.
+ */
+void Untar_ChunkContext_Init(Untar_ChunkContext *context);
+
+/*
+ * @brief Rips links, directories and files out of a part of a block of memory.
+ *
+ * @param Untar_ChunkContext *context [in] Pointer to a context structure.
+ * @param void *chunk [in] Pointer to a chunk of a TAR buffer.
+ * @param size_t chunk_size [in] Length of the chunk of a TAR buffer.
+ *
+ * @retval UNTAR_SUCCESSFUL (0)    on successful completion.
+ * @retval UNTAR_FAIL              for a faulty step within the process.
+ * @retval UNTAR_INVALID_CHECKSUM  for an invalid header checksum.
+ * @retval UNTAR_INVALID_HEADER    for an invalid header.
+ */
+
+int Untar_FromChunk_Print(
+  Untar_ChunkContext *context,
+  void *chunk,
+  size_t chunk_size,
+  const rtems_printer* printer
+);
+
 /**************************************************************************
  * This converts octal ASCII number representations into an
  * unsigned long.  Only support 32-bit numbers for now.