[haiku-commits] r35812 - haiku/trunk/src/system/boot/loader
- From: ingo_weinhold@xxxxxx
- To: haiku-commits@xxxxxxxxxxxxx
- Date: Thu, 11 Mar 2010 18:09:12 +0100 (CET)
Author: bonefish
Date: 2010-03-11 18:09:11 +0100 (Thu, 11 Mar 2010)
New Revision: 35812
Changeset: http://dev.haiku-os.org/changeset/35812/haiku
Added:
haiku/trunk/src/system/boot/loader/pager.cpp
haiku/trunk/src/system/boot/loader/pager.h
Log:
A simple pager implemented on top of the generic text console interface.
Added: haiku/trunk/src/system/boot/loader/pager.cpp
===================================================================
--- haiku/trunk/src/system/boot/loader/pager.cpp
(rev 0)
+++ haiku/trunk/src/system/boot/loader/pager.cpp 2010-03-11 17:09:11 UTC
(rev 35812)
@@ -0,0 +1,207 @@
+/*
+ * Copyright 2010, Ingo Weinhold, ingo_weinhold@xxxxxxx
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "pager.h"
+
+#include <ctype.h>
+#include <string.h>
+
+#include <algorithm>
+
+#include <boot/platform/generic/text_console.h>
+
+
+// #pragma mark - PagerTextSource
+
+
+PagerTextSource::~PagerTextSource()
+{
+}
+
+
+// #pragma mark -
+
+
+static size_t
+next_line(const PagerTextSource& textSource, size_t width, size_t offset,
+ char* buffer, size_t bufferSize)
+{
+ size_t bytesRead = textSource.Read(offset, buffer, bufferSize - 1);
+ if (bytesRead == 0)
+ return 0;
+
+ buffer[bytesRead] = '\0';
+
+ // replace all '\0's by spaces
+ for (size_t i = 0; i < bytesRead; i++) {
+ if (buffer[i] == '\0')
+ buffer[i] = ' ';
+ }
+
+ if (const char* lineEnd = strchr(buffer, '\n'))
+ bytesRead = lineEnd - buffer;
+
+ if (bytesRead > (size_t)width)
+ bytesRead = width;
+
+ // replace unprintables by '.'
+ for (size_t i = 0; i < bytesRead; i++) {
+ if (!isprint(buffer[i]))
+ buffer[i] = '.';
+ }
+
+ bool lineBreak = buffer[bytesRead] == '\n';
+
+ buffer[bytesRead] = '\0';
+
+ return bytesRead + (lineBreak ? 1 : 0);
+}
+
+
+static int32
+count_lines(const PagerTextSource& textSource, size_t width, char* buffer,
+ size_t bufferSize)
+{
+ int32 lineCount = 0;
+ size_t offset = 0;
+
+ while (true) {
+ size_t bytesRead = next_line(textSource, width, offset, buffer,
+ bufferSize);
+ if (bytesRead == 0)
+ break;
+
+ offset += bytesRead;
+ lineCount++;
+ }
+
+ return lineCount;
+}
+
+
+static size_t
+offset_of_line(const PagerTextSource& textSource, size_t width, char* buffer,
+ size_t bufferSize, int32 line)
+{
+ int32 lineCount = 0;
+ size_t offset = 0;
+
+ while (true) {
+ if (line == lineCount)
+ return offset;
+
+ size_t bytesRead = next_line(textSource, width, offset, buffer,
+ bufferSize);
+ if (bytesRead == 0)
+ break;
+
+ offset += bytesRead;
+ lineCount++;
+ }
+
+ return offset;
+}
+
+
+// #pragma mark -
+
+
+void
+pager(const PagerTextSource& textSource)
+{
+ console_set_cursor(0, 0);
+
+ int32 width = console_width();
+ int32 height = console_height();
+
+ char lineBuffer[256];
+
+ int32 lineCount = count_lines(textSource, width, lineBuffer,
+ sizeof(lineBuffer));
+ int32 topLine = 0;
+
+ bool quit = false;
+ while (!quit) {
+ // get the text offset for the top line
+ size_t offset = offset_of_line(textSource, width, lineBuffer,
+ sizeof(lineBuffer), topLine);
+
+ // clear the screen and print the lines
+ console_clear_screen();
+
+ int32 screenLine = 0;
+ while (screenLine + 1 < height) {
+ size_t bytesRead = next_line(textSource, width, offset,
lineBuffer,
+ sizeof(lineBuffer));
+ if (bytesRead == 0)
+ break;
+
+ console_set_cursor(0, screenLine);
+ puts(lineBuffer);
+
+ offset += bytesRead;
+ screenLine++;
+ }
+
+ // print the statistics line at the bottom
+ console_set_cursor(0, height - 1);
+ console_set_color(BLACK, WHITE);
+ int32 bottomLine = std::min(topLine + height - 2, lineCount -
1);
+ printf("%" B_PRIuSIZE " - %" B_PRIuSIZE " %" B_PRIuSIZE "%%",
+ topLine, bottomLine, (bottomLine + 1) * 100 /
lineCount);
+ console_set_color(WHITE, BLACK);
+
+ // wait for a key that changes the position
+ int32 previousTopLine = topLine;
+
+ while (!quit && topLine == previousTopLine) {
+ switch (console_wait_for_key()) {
+ case TEXT_CONSOLE_KEY_ESCAPE:
+ case 'q':
+ case 'Q':
+ // quit
+ quit = true;
+ break;
+
+ case TEXT_CONSOLE_KEY_DOWN:
+ case TEXT_CONSOLE_KEY_RETURN:
+ // next line
+ topLine++;
+ break;
+
+ case TEXT_CONSOLE_KEY_UP:
+ // previous line
+ topLine--;
+ break;
+
+ case TEXT_CONSOLE_KEY_PAGE_UP:
+ // previous page
+ topLine -= height - 1;
+ break;
+
+ case TEXT_CONSOLE_KEY_PAGE_DOWN:
+ // next page
+ topLine += height - 1;
+ break;
+
+ case TEXT_CONSOLE_KEY_HOME:
+ // beginning of text
+ topLine = 0;
+ break;
+
+ case TEXT_CONSOLE_KEY_END:
+ // end of text
+ topLine = lineCount;
+ break;
+ }
+
+ if (topLine > lineCount - (height - 1))
+ topLine = lineCount - (height - 1);
+ if (topLine < 0)
+ topLine = 0;
+ }
+ }
+}
Added: haiku/trunk/src/system/boot/loader/pager.h
===================================================================
--- haiku/trunk/src/system/boot/loader/pager.h (rev 0)
+++ haiku/trunk/src/system/boot/loader/pager.h 2010-03-11 17:09:11 UTC (rev
35812)
@@ -0,0 +1,25 @@
+/*
+ * Copyright 2010, Ingo Weinhold, ingo_weinhold@xxxxxxx
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef PAGER_H
+#define PAGER_H
+
+
+#include <SupportDefs.h>
+
+
+class PagerTextSource {
+public:
+ virtual ~PagerTextSource();
+
+ virtual size_t BytesAvailable() const = 0;
+ virtual size_t Read(size_t offset, void*
buffer,
+ size_t
size) const = 0;
+};
+
+
+void pager(const PagerTextSource& textSource);
+
+
+#endif // PAGER_H
Other related posts:
- » [haiku-commits] r35812 - haiku/trunk/src/system/boot/loader - ingo_weinhold
