add libtransmission/file.c

libtransmission/file.c

@@ -0,0 +1,123 @@
+/*
+ * This file Copyright (C) 2013-2014 Mnemosyne LLC
+ *
+ * It may be used under the GNU GPL versions 2 or 3
+ * or any future license endorsed by Mnemosyne LLC.
+ *
+ * $Id$
+ */
+
+#include <assert.h>
+#include <string.h> /* strlen () */
+
+#include "transmission.h"
+#include "file.h"
+#include "utils.h"
+
+bool
+tr_sys_file_read_line (tr_sys_file_t    handle,
+                       char           * buffer,
+                       size_t           buffer_size,
+                       tr_error      ** error)
+{
+  bool ret = false;
+  size_t offset = 0;
+  uint64_t bytes_read;
+
+  assert (handle != TR_BAD_SYS_FILE);
+  assert (buffer != NULL);
+  assert (buffer_size > 0);
+
+  while (buffer_size > 0)
+    {
+      size_t i;
+      bool found_eol = false;
+
+      ret = tr_sys_file_read (handle, buffer + offset, MIN(buffer_size, 1024u),
+                              &bytes_read, error);
+      if (!ret || (offset == 0 && bytes_read == 0))
+        {
+          ret = false;
+          break;
+        }
+
+      for (i = 0; i < bytes_read; ++i, ++offset, --buffer_size)
+        {
+          if (buffer[offset] == '\n')
+            {
+              found_eol = true;
+              break;
+            }
+        }
+
+      if (found_eol || buffer_size == 0 || bytes_read == 0)
+        {
+          const int64_t delta = -(int64_t) bytes_read + i + (found_eol ? 1 : 0);
+
+          if (delta != 0)
+            {
+              ret = tr_sys_file_seek (handle, delta, TR_SEEK_CUR, NULL, error);
+              if (!ret)
+                break;
+            }
+
+          if (offset > 0 && buffer[offset - 1] == '\r')
+            buffer[offset - 1] = '\0';
+          else
+            buffer[offset] = '\0';
+
+          break;
+        }
+    }
+
+  return ret;
+}
+
+bool
+tr_sys_file_write_line (tr_sys_file_t    handle,
+                        const char     * buffer,
+                        tr_error      ** error)
+{
+  bool ret;
+
+  assert (handle != TR_BAD_SYS_FILE);
+  assert (buffer != NULL);
+
+  ret = tr_sys_file_write (handle, buffer, strlen (buffer), NULL, error);
+
+  if (ret)
+    ret = tr_sys_file_write (handle, TR_NATIVE_EOL_STR, TR_NATIVE_EOL_STR_SIZE,
+                             NULL, error);
+
+  return ret;
+}
+
+bool
+tr_sys_file_write_fmt (tr_sys_file_t    handle,
+                       const char     * format,
+                       tr_error      ** error,
+                                        ...)
+{
+  bool ret = false;
+  char * buffer;
+  va_list args;
+
+  assert (handle != TR_BAD_SYS_FILE);
+  assert (format != NULL);
+
+  va_start (args, error);
+  buffer = tr_strdup_vprintf (format, args);
+  va_end (args);
+
+  if (buffer != NULL)
+    {
+      ret = tr_sys_file_write (handle, buffer, strlen (buffer), NULL, error);
+      tr_free (buffer);
+    }
+  else
+    {
+      tr_error_set_literal (error, 0, "Unable to format message.");
+    }
+
+  return ret;
+}