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-rw-r--r--src/viewer/growbuf.c297
1 files changed, 297 insertions, 0 deletions
diff --git a/src/viewer/growbuf.c b/src/viewer/growbuf.c
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--- /dev/null
+++ b/src/viewer/growbuf.c
@@ -0,0 +1,297 @@
+/*
+ Internal file viewer for the Midnight Commander
+ Function for work with growing buffers
+
+ Copyright (C) 1994-2023
+ Free Software Foundation, Inc.
+
+ Written by:
+ Miguel de Icaza, 1994, 1995, 1998
+ Janne Kukonlehto, 1994, 1995
+ Jakub Jelinek, 1995
+ Joseph M. Hinkle, 1996
+ Norbert Warmuth, 1997
+ Pavel Machek, 1998
+ Roland Illig <roland.illig@gmx.de>, 2004, 2005
+ Slava Zanko <slavazanko@google.com>, 2009
+ Andrew Borodin <aborodin@vmail.ru>, 2009, 2014
+ Ilia Maslakov <il.smind@gmail.com>, 2009
+
+ This file is part of the Midnight Commander.
+
+ The Midnight Commander is free software: you can redistribute it
+ and/or modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation, either version 3 of the License,
+ or (at your option) any later version.
+
+ The Midnight Commander is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <errno.h>
+
+#include "lib/global.h"
+#include "lib/vfs/vfs.h"
+#include "lib/util.h"
+#include "lib/widget.h" /* D_NORMAL */
+
+#include "internal.h"
+
+/* Block size for reading files in parts */
+#define VIEW_PAGE_SIZE ((size_t) 8192)
+
+/*** global variables ****************************************************************************/
+
+/*** file scope macro definitions ****************************************************************/
+
+/*** file scope type declarations ****************************************************************/
+
+/*** file scope variables ************************************************************************/
+
+/*** file scope functions ************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_growbuf_init (WView * view)
+{
+ view->growbuf_in_use = TRUE;
+ view->growbuf_blockptr = g_ptr_array_new_with_free_func (g_free);
+ view->growbuf_lastindex = VIEW_PAGE_SIZE;
+ view->growbuf_finished = FALSE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_growbuf_done (WView * view)
+{
+ view->growbuf_finished = TRUE;
+
+ if (view->datasource == DS_STDIO_PIPE)
+ {
+ mc_pclose (view->ds_stdio_pipe, NULL);
+ view->ds_stdio_pipe = NULL;
+ }
+ else /* view->datasource == DS_VFS_PIPE */
+ {
+ (void) mc_close (view->ds_vfs_pipe);
+ view->ds_vfs_pipe = -1;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mcview_growbuf_free (WView * view)
+{
+ g_assert (view->growbuf_in_use);
+
+ g_ptr_array_free (view->growbuf_blockptr, TRUE);
+ view->growbuf_blockptr = NULL;
+ view->growbuf_in_use = FALSE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+off_t
+mcview_growbuf_filesize (WView * view)
+{
+ g_assert (view->growbuf_in_use);
+
+ if (view->growbuf_blockptr->len == 0)
+ return 0;
+ else
+ return ((off_t) view->growbuf_blockptr->len - 1) * VIEW_PAGE_SIZE + view->growbuf_lastindex;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/** Copies the output from the pipe to the growing buffer, until either
+ * the end-of-pipe is reached or the interval [0..ofs) of the growing
+ * buffer is completely filled.
+ */
+
+void
+mcview_growbuf_read_until (WView * view, off_t ofs)
+{
+ gboolean short_read = FALSE;
+
+ g_assert (view->growbuf_in_use);
+
+ if (view->growbuf_finished)
+ return;
+
+ while (mcview_growbuf_filesize (view) < ofs || short_read)
+ {
+ ssize_t nread = 0;
+ byte *p;
+ size_t bytesfree;
+
+ if (view->growbuf_lastindex == VIEW_PAGE_SIZE)
+ {
+ /* Append a new block to the growing buffer */
+ byte *newblock = g_try_malloc (VIEW_PAGE_SIZE);
+ if (newblock == NULL)
+ return;
+
+ g_ptr_array_add (view->growbuf_blockptr, newblock);
+ view->growbuf_lastindex = 0;
+ }
+
+ p = (byte *) g_ptr_array_index (view->growbuf_blockptr,
+ view->growbuf_blockptr->len - 1) + view->growbuf_lastindex;
+
+ bytesfree = VIEW_PAGE_SIZE - view->growbuf_lastindex;
+
+ if (view->datasource == DS_STDIO_PIPE)
+ {
+ mc_pipe_t *sp = view->ds_stdio_pipe;
+ GError *error = NULL;
+
+ if (bytesfree > MC_PIPE_BUFSIZE)
+ bytesfree = MC_PIPE_BUFSIZE;
+
+ sp->out.len = bytesfree;
+ sp->err.len = MC_PIPE_BUFSIZE;
+
+ mc_pread (sp, &error);
+
+ if (error != NULL)
+ {
+ mcview_show_error (view, error->message);
+ g_error_free (error);
+ mcview_growbuf_done (view);
+ return;
+ }
+
+ if (view->pipe_first_err_msg && sp->err.len > 0)
+ {
+ /* ignore possible following errors */
+ /* reset this flag before call of mcview_show_error() to break
+ * endless recursion: mcview_growbuf_read_until() -> mcview_show_error() ->
+ * MSG_DRAW -> mcview_display() -> mcview_get_byte() -> mcview_growbuf_read_until()
+ */
+ view->pipe_first_err_msg = FALSE;
+
+ mcview_show_error (view, sp->err.buf);
+
+ /* when switch from parse to raw mode and back,
+ * do not close the already closed pipe (see call to mcview_growbuf_done below).
+ * return from here since (sp == view->ds_stdio_pipe) would now be invalid.
+ * NOTE: this check was removed by ticket #4103 but the above call to
+ * mcview_show_error triggers the stdio pipe handle to be closed:
+ * mcview_close_datasource -> mcview_growbuf_done
+ */
+ if (view->ds_stdio_pipe == NULL)
+ return;
+ }
+
+ if (sp->out.len > 0)
+ {
+ memmove (p, sp->out.buf, sp->out.len);
+ nread = sp->out.len;
+ }
+ else if (sp->out.len == MC_PIPE_STREAM_EOF || sp->out.len == MC_PIPE_ERROR_READ)
+ {
+ if (sp->out.len == MC_PIPE_ERROR_READ)
+ {
+ char *err_msg;
+
+ err_msg = g_strdup_printf (_("Failed to read data from child stdout:\n%s"),
+ unix_error_string (sp->out.error));
+ mcview_show_error (view, err_msg);
+ g_free (err_msg);
+ }
+
+ /* when switch from parse to raw mode and back,
+ * do not close the already closed pipe after following loop:
+ * mcview_growbuf_read_until() -> mcview_show_error() ->
+ * MSG_DRAW -> mcview_display() -> mcview_get_byte() -> mcview_growbuf_read_until()
+ */
+ mcview_growbuf_done (view);
+
+ mcview_display (view);
+ return;
+ }
+ }
+ else
+ {
+ g_assert (view->datasource == DS_VFS_PIPE);
+ do
+ {
+ nread = mc_read (view->ds_vfs_pipe, p, bytesfree);
+ }
+ while (nread == -1 && errno == EINTR);
+
+ if (nread <= 0)
+ {
+ mcview_growbuf_done (view);
+ return;
+ }
+ }
+ short_read = ((size_t) nread < bytesfree);
+ view->growbuf_lastindex += nread;
+ }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+gboolean
+mcview_get_byte_growing_buffer (WView * view, off_t byte_index, int *retval)
+{
+ char *p;
+
+ g_assert (view->growbuf_in_use);
+
+ if (retval != NULL)
+ *retval = -1;
+
+ if (byte_index < 0)
+ return FALSE;
+
+ p = mcview_get_ptr_growing_buffer (view, byte_index);
+ if (p == NULL)
+ return FALSE;
+
+ if (retval != NULL)
+ *retval = (unsigned char) (*p);
+
+ return TRUE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+char *
+mcview_get_ptr_growing_buffer (WView * view, off_t byte_index)
+{
+ off_t pageno, pageindex;
+
+ g_assert (view->growbuf_in_use);
+
+ if (byte_index < 0)
+ return NULL;
+
+ pageno = byte_index / VIEW_PAGE_SIZE;
+ pageindex = byte_index % VIEW_PAGE_SIZE;
+
+ mcview_growbuf_read_until (view, byte_index + 1);
+ if (view->growbuf_blockptr->len == 0)
+ return NULL;
+ if (pageno < (off_t) view->growbuf_blockptr->len - 1)
+ return ((char *) g_ptr_array_index (view->growbuf_blockptr, pageno) + pageindex);
+ if (pageno == (off_t) view->growbuf_blockptr->len - 1
+ && pageindex < (off_t) view->growbuf_lastindex)
+ return ((char *) g_ptr_array_index (view->growbuf_blockptr, pageno) + pageindex);
+ return NULL;
+}
+
+/* --------------------------------------------------------------------------------------------- */
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