Changeset 178 for trunk/lib

Timestamp:

03/13/10 12:56:36 (15 years ago)

Author:

tim

Message:

reworked I/O to use callback functions

fixed a bug in mtime validation and consolidated time formatting code

File:

• trunk/lib/regfi.c (modified) (37 diffs)

trunk/lib/regfi.c

@@ -422 +422 @@
 
 
+off_t regfi_raw_seek(REGFI_RAW_FILE* self, off_t offset, int whence)
+{
+  return lseek(*(int*)self->state, offset, whence);
+}
+
+ssize_t regfi_raw_read(REGFI_RAW_FILE* self, void* buf, size_t count)
+{
+  return read(*(int*)self->state, buf, count);
+}
+
+
+/*****************************************************************************
+ * Convenience function to wrap up the ugly callback stuff
+ *****************************************************************************/
+off_t regfi_seek(REGFI_RAW_FILE* file_cb, off_t offset, int whence)
+{
+  return file_cb->seek(file_cb, offset, whence);
+}
+
+
 /*****************************************************************************
  * This function is just like read(2), except that it continues to
  * re-try reading from the file descriptor if EINTR or EAGAIN is received.  
- * regfi_read will attempt to read length bytes from fd and write them to buf.
+ * regfi_read will attempt to read length bytes from the file and write them to
+ * buf.
  *
  * On success, 0 is returned.  Upon failure, an errno code is returned.
@@ -433 +454 @@
  * returned as 0, then EOF was encountered immediately
  *****************************************************************************/
-uint32_t regfi_read(int fd, uint8_t* buf, uint32_t* length)
+uint32_t regfi_read(REGFI_RAW_FILE* file_cb, uint8_t* buf, uint32_t* length)
 {
   uint32_t rsize = 0;
@@ -440 +461 @@
   do
   {
-    rret = read(fd, buf + rsize, *length - rsize);
+    rret = file_cb->read(file_cb, buf + rsize, *length - rsize);
     if(rret > 0)
       rsize += rret;
@@ -457 +478 @@
  *
  *****************************************************************************/
-bool regfi_parse_cell(int fd, uint32_t offset, uint8_t* hdr, uint32_t hdr_len,
-                      uint32_t* cell_length, bool* unalloc)
+bool regfi_parse_cell(REGFI_RAW_FILE* file_cb, uint32_t offset, uint8_t* hdr, 
+                      uint32_t hdr_len, uint32_t* cell_length, bool* unalloc)
 {
   uint32_t length;
@@ -464 +485 @@
   uint8_t tmp[4];
 
-  if(lseek(fd, offset, SEEK_SET) == -1)
+  if(regfi_seek(file_cb, offset, SEEK_SET) == -1)
     return false;
 
   length = 4;
-  if((regfi_read(fd, tmp, &length) != 0) || length != 4)
+  if((regfi_read(file_cb, tmp, &length) != 0) || length != 4)
     return false;
   raw_length = IVALS(tmp, 0);
@@ -489 +510 @@
   {
     length = hdr_len;
-    if((regfi_read(fd, hdr, &length) != 0) || length != hdr_len)
+    if((regfi_read(file_cb, hdr, &length) != 0) || length != hdr_len)
       return false;
   }
@@ -634 +655 @@
   bool recursive_type;
 
-  if(!regfi_parse_cell(file->fd, offset, buf, REGFI_SUBKEY_LIST_MIN_LEN, 
+  if(!regfi_parse_cell(file->cb, offset, buf, REGFI_SUBKEY_LIST_MIN_LEN,
                        &cell_length, &unalloc))
   {
@@ -704 +725 @@
 
   read_len = length;
-  if(regfi_read(file->fd, elements, &read_len) != 0 || read_len != length)
+  if(regfi_read(file->cb, elements, &read_len) != 0 || read_len!=length)
     goto fail;
 
@@ -802 +823 @@
   bool unalloc = false;
 
-  if(!regfi_parse_cell(file->fd, offset, sk_header, REGFI_SK_MIN_LENGTH,
+  if(!regfi_parse_cell(file->cb, offset, sk_header, REGFI_SK_MIN_LENGTH,
                        &cell_length, &unalloc))
   {
@@ -868 +889 @@
 
   length = ret_val->desc_size;
-  if(regfi_read(file->fd, sec_desc_buf, &length) != 0 
+  if(regfi_read(file->cb, sec_desc_buf, &length) != 0 
      || length != ret_val->desc_size)
   {
@@ -904 +925 @@
   bool unalloc;
 
-  if(!regfi_parse_cell(file->fd, offset, NULL, 0, &cell_length, &unalloc))
+  if(!regfi_parse_cell(file->cb, offset, NULL, 0, &cell_length, &unalloc))
   {
     regfi_add_message(file, REGFI_MSG_ERROR, "Failed to read cell header"
@@ -943 +964 @@
 
   length = read_len;
-  if((regfi_read(file->fd, (uint8_t*)ret_val->elements, &length) != 0) 
+  if((regfi_read(file->cb, (uint8_t*)ret_val->elements, &length) != 0) 
      || length != read_len)
   {
@@ -1265 +1286 @@
   while(cur_offset < hbin_end)
   {
-    if(!regfi_parse_cell(file->fd, cur_offset, NULL, 0, &cell_length, &unalloc))
+    if(!regfi_parse_cell(file->cb, cur_offset, NULL, 0, &cell_length, &unalloc))
     {
       regfi_add_message(file, REGFI_MSG_WARN, "Could not parse cell at offset"
@@ -1289 +1310 @@
 
 
-/******************************************************************************
- ******************************************************************************/
-REGFI_FILE* regfi_open(const char* filename)
-{
-  REGFI_FILE* ret_val;
-  int fd;
-
-  /* open an existing file */
-  if ((fd = open(filename, REGFI_OPEN_FLAGS)) == -1)
-  {
-    /* fprintf(stderr, "regfi_open: failure to open %s (%s)\n", filename, strerror(errno));*/
-    return NULL;
-  }
-
-  ret_val = regfi_alloc(fd);
-
-  if(ret_val == NULL)
-    close(fd);
-
-  return ret_val;
-}
-
 
 /******************************************************************************
@@ -1316 +1315 @@
 REGFI_FILE* regfi_alloc(int fd)
 {
-  struct stat sbuf;
+  REGFI_FILE* ret_val;
+  REGFI_RAW_FILE* file_cb = talloc(NULL, REGFI_RAW_FILE);
+  if(file_cb == NULL) 
+    return NULL;
+
+  file_cb->state = (void*)talloc(file_cb, int);
+  if(file_cb->state == NULL)
+    goto fail;
+  *(int*)file_cb->state = fd;
+  
+  file_cb->cur_off = 0;
+  file_cb->size = 0;
+  file_cb->read = &regfi_raw_read;
+  file_cb->seek = &regfi_raw_seek;
+  
+  ret_val = regfi_alloc_cb(file_cb);
+  if(ret_val == NULL)
+    goto fail;
+
+  /* In this case, we want file_cb to be freed when ret_val is */
+  talloc_steal(ret_val, file_cb);
+  return ret_val;
+
+ fail:
+    talloc_free(file_cb);
+    return NULL;
+}
+
+
+
+REGFI_FILE* regfi_alloc_cb(REGFI_RAW_FILE* file_cb)
+{
   REGFI_FILE* rb;
   REGFI_HBIN* hbin = NULL;
-  uint32_t hbin_off, file_length, cache_secret;
+  uint32_t hbin_off, cache_secret;
+  int32_t file_length;
   bool rla;
 
-  /* Determine file length.  Must be at least big enough 
-   * for the header and one hbin. 
+  /* Determine file length.  Must be at least big enough for the header
+   * and one hbin.
    */
-  if (fstat(fd, &sbuf) == -1)
-    return NULL;
-  file_length = sbuf.st_size;
+  file_length = file_cb->seek(file_cb, 0, SEEK_END);
   if(file_length < REGFI_REGF_SIZE+REGFI_HBIN_ALLOC)
     return NULL;
+  file_cb->seek(file_cb, 0, SEEK_SET);
 
   /* Read file header */
-  if ((rb = regfi_parse_regf(fd, true)) == NULL) 
-  {
-    /* fprintf(stderr, "regfi_alloc: Failed to read initial REGF block\n"); */
+  if ((rb = regfi_parse_regf(file_cb, true)) == NULL) 
+  {
+    /* fprintf(stderr, "regfi_alloc_cb: Failed to read initial REGF block\n");*/
     return NULL;
   }
   rb->file_length = file_length;  
+  rb->cb = file_cb;
 
   rb->hbins = range_list_new();
   if(rb->hbins == NULL)
   {
-    /* fprintf(stderr, "regfi_alloc: Failed to create HBIN list.\n"); */
+    /* fprintf(stderr, "regfi_alloc_cb: Failed to create HBIN list.\n"); */
     talloc_free(rb);
     return NULL;
@@ -1374 +1405 @@
   /* success */
   return rb;
-}
-
-
-/******************************************************************************
- ******************************************************************************/
-int regfi_close(REGFI_FILE* file)
-{
-  int fd;
-
-  /* nothing to do if there is no open file */
-  if ((file == NULL) || (file->fd == -1))
-    return 0;
-
-  fd = file->fd;
-  file->fd = -1;
-
-  regfi_free(file);
-
-  return close(fd);
 }
 
@@ -2183 +2195 @@
  * XXX: Add way to return more detailed error information.
  *******************************************************************/
-REGFI_FILE* regfi_parse_regf(int fd, bool strict)
+REGFI_FILE* regfi_parse_regf(REGFI_RAW_FILE* file_cb, bool strict)
 {
   uint8_t file_header[REGFI_REGF_SIZE];
@@ -2193 +2205 @@
     return NULL;
 
-  ret_val->fd = fd;
   ret_val->sk_cache = NULL;
   ret_val->last_message = NULL;
   ret_val->hbins = NULL;
-  
+
   length = REGFI_REGF_SIZE;
-  if((regfi_read(fd, file_header, &length)) != 0 || length != REGFI_REGF_SIZE)
+  if((regfi_read(file_cb, file_header, &length)) != 0 
+     || length != REGFI_REGF_SIZE)
     goto fail;
   
@@ -2217 +2229 @@
                       ret_val->magic[2], ret_val->magic[3]);
   }
+
   ret_val->sequence1 = IVAL(file_header, 0x4);
   ret_val->sequence2 = IVAL(file_header, 0x8);
@@ -2270 +2283 @@
     return NULL;
 
-  if(lseek(file->fd, offset, SEEK_SET) == -1)
+  if(regfi_seek(file->cb, offset, SEEK_SET) == -1)
   {
     regfi_add_message(file, REGFI_MSG_ERROR, "Seek failed"
@@ -2278 +2291 @@
 
   length = REGFI_HBIN_HEADER_SIZE;
-  if((regfi_read(file->fd, hbin_header, &length) != 0) 
+  if((regfi_read(file->cb, hbin_header, &length) != 0) 
      || length != REGFI_HBIN_HEADER_SIZE)
     return NULL;
 
-  if(lseek(file->fd, offset, SEEK_SET) == -1)
+  if(regfi_seek(file->cb, offset, SEEK_SET) == -1)
   {
     regfi_add_message(file, REGFI_MSG_ERROR, "Seek failed"
@@ -2341 +2354 @@
   bool unalloc = false;
 
-  if(!regfi_parse_cell(file->fd, offset, nk_header, REGFI_NK_MIN_LENGTH,
+  if(!regfi_parse_cell(file->cb, offset, nk_header, REGFI_NK_MIN_LENGTH,
                        &cell_length, &unalloc))
   {
@@ -2399 +2412 @@
    */
   if(unalloc
-     && ((ret_val->mtime.high < REGFI_MTIME_MIN_HIGH 
-          && ret_val->mtime.low < REGFI_MTIME_MIN_LOW)
-         || (ret_val->mtime.high > REGFI_MTIME_MAX_HIGH 
-             && ret_val->mtime.low > REGFI_MTIME_MAX_LOW)))
-    return NULL;
+     && (ret_val->mtime.high < REGFI_MTIME_MIN_HIGH 
+         || ret_val->mtime.high > REGFI_MTIME_MAX_HIGH))
+  {
+    talloc_free(ret_val);
+    return NULL;
+  }
 
   ret_val->unknown1 = IVAL(nk_header, 0xC);
@@ -2459 +2473 @@
   /* Don't need to seek, should be at the right offset */
   length = ret_val->name_length;
-  if((regfi_read(file->fd, (uint8_t*)ret_val->keyname_raw, &length) != 0)
+  if((regfi_read(file->cb, (uint8_t*)ret_val->keyname_raw, &length) != 0)
      || length != ret_val->name_length)
   {
@@ -2483 +2497 @@
      && (offset & 0x00000007) == 0)
   {
-    if(!regfi_parse_cell(file->fd, offset, NULL, 0, &cell_length, &unalloc))
+    if(!regfi_parse_cell(file->cb, offset, NULL, 0, &cell_length, &unalloc))
     {
       regfi_add_message(file, REGFI_MSG_WARN, "Could not parse cell header"
@@ -2521 +2535 @@
     {
       length = *name_length;
-      if((regfi_read(file->fd, ret_val, &length) != 0)
+      if((regfi_read(file->cb, ret_val, &length) != 0)
          || length != *name_length)
       {
@@ -2546 +2560 @@
   bool unalloc = false;
 
-  if(!regfi_parse_cell(file->fd, offset, vk_header, REGFI_VK_MIN_LENGTH,
+  if(!regfi_parse_cell(file->cb, offset, vk_header, REGFI_VK_MIN_LENGTH,
                        &cell_length, &unalloc))
   {
@@ -2629 +2643 @@
 
     length = ret_val->name_length;
-    if((regfi_read(file->fd, (uint8_t*)ret_val->valuename_raw, &length) != 0)
+    if((regfi_read(file->cb, (uint8_t*)ret_val->valuename_raw, &length) != 0)
        || length != ret_val->name_length)
     {
@@ -2697 +2711 @@
     }
     
-    if(!regfi_parse_cell(file->fd, offset, NULL, 0,
+    if(!regfi_parse_cell(file->cb, offset, NULL, 0,
                          &cell_length, &unalloc))
     {
@@ -2770 +2784 @@
   ret_val.len = 0;
   
-  if(lseek(file->fd, offset+4, SEEK_SET) == -1)
+  if(regfi_seek(file->cb, offset+4, SEEK_SET) == -1)
   {
     regfi_add_message(file, REGFI_MSG_WARN, "Could not seek while "
@@ -2782 +2796 @@
   
   read_length = length;
-  if((regfi_read(file->fd, ret_val.buf, &read_length) != 0)
+  if((regfi_read(file->cb, ret_val.buf, &read_length) != 0)
      || read_length != length)
   {
@@ -2848 +2862 @@
   }
 
-  if(!regfi_parse_cell(file->fd, offset, ret_val.buf, REGFI_BIG_DATA_MIN_LENGTH,
+  if(!regfi_parse_cell(file->cb, offset, ret_val.buf, REGFI_BIG_DATA_MIN_LENGTH,
                        &cell_length, &unalloc))
   {
@@ -2902 +2916 @@
     goto fail;
 
-  if(!regfi_parse_cell(file->fd, offset, (uint8_t*)ret_val,
+  if(!regfi_parse_cell(file->cb, offset, (uint8_t*)ret_val,
                        num_chunks*sizeof(uint32_t),
                        &indirect_length, &unalloc))
@@ -2957 +2971 @@
   {
     chunk_offset = offsets[i]+REGFI_REGF_SIZE;
-    if(!regfi_parse_cell(file->fd, chunk_offset, NULL, 0,
+    if(!regfi_parse_cell(file->cb, chunk_offset, NULL, 0,
                          &cell_length, &unalloc))
     {
@@ -3065 +3079 @@
     }
 
-    if(lseek(file->fd, cell_info->offset+sizeof(uint32_t), SEEK_SET) == -1)
+    if(regfi_seek(file->cb, cell_info->offset+sizeof(uint32_t), SEEK_SET) == -1)
     {
       regfi_add_message(file, REGFI_MSG_WARN, "Could not seek to chunk while "
@@ -3074 +3088 @@
 
     tmp_len = read_length;
-    if(regfi_read(file->fd, ret_val.buf+(data_length-data_left), 
+    if(regfi_read(file->cb, ret_val.buf+(data_length-data_left), 
                   &read_length) != 0 || (read_length != tmp_len))
     {
@@ -3130 +3144 @@
     while(curr_off < hbin->block_size)
     {
-      if(!regfi_parse_cell(file->fd, hbin->file_off+curr_off, NULL, 0,
+      if(!regfi_parse_cell(file->cb, hbin->file_off+curr_off, NULL, 0,
                            &cell_len, &is_unalloc))
         break;