Squash commits for public release

userland/utilities/edit/file.c

@@ -0,0 +1,176 @@
+#include "file.h"
+#include "viewer.h"
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+file_view_area_t view_area;
+
+static int _file_get_size_of_first_line()
+{
+    int res = 0;
+    for (int i = view_area.start; i < view_area.data_len; i++) {
+        res++;
+        if (view_area.buffer[i] == '\n') {
+            return res;
+        }
+    }
+    return view_area.data_len - view_area.start;
+}
+
+static void _file_find_start(uint32_t old_offset)
+{
+    old_offset -= 2;
+    while (old_offset > view_area.offset) {
+        if (view_area.buffer[old_offset - view_area.offset] == '\n') {
+            view_area.start = old_offset - view_area.offset + 1;
+            return;
+        }
+        old_offset--;
+    }
+    view_area.start = 0;
+}
+
+static inline int _file_remaining_size()
+{
+    return view_area.data_len - view_area.start;
+}
+
+static inline int _file_is_last_line_in_buf()
+{
+    return 1;
+}
+
+int _file_buf_flush()
+{
+    /* FIXME: for now we think that we have all file in our buffer */
+    lseek(view_area.fd, view_area.offset, SEEK_SET);
+    view_area.data_len = write(view_area.fd, view_area.buffer, view_area.data_len);
+    return 0;
+}
+
+int _file_buf_reload(int offset_in_file)
+{
+    /* TODO: Get real file size */
+    view_area.buf_len = 4000;
+    view_area.buffer = (char*)malloc(view_area.buf_len);
+
+    view_area.start = 0;
+    view_area.offset = offset_in_file;
+    view_area.was_changed = 0;
+    lseek(view_area.fd, view_area.offset, SEEK_SET);
+    view_area.data_len = read(view_area.fd, view_area.buffer, view_area.buf_len);
+    if (view_area.data_len < 0) {
+        return -1;
+    }
+    return 0;
+}
+
+int file_line_len(int offset)
+{
+    int res = 0;
+    for (int i = offset; i < view_area.data_len; i++) {
+        res++;
+        if (view_area.buffer[i] == '\n') {
+            return res;
+        }
+    }
+    return view_area.data_len - view_area.start;
+}
+
+int file_line_len_backwards(int offset)
+{
+
+    int res = 1;
+    for (int i = offset - 1; i >= view_area.offset; i--) {
+        if (view_area.buffer[i] == '\n') {
+            return res;
+        }
+        res++;
+    }
+    return offset;
+}
+
+int file_open(char* path)
+{
+    int n;
+    if ((view_area.fd = open(path, O_RDWR)) < 0) {
+        return -1;
+    }
+
+    _file_buf_reload(0);
+    if (view_area.data_len < 0) {
+        return -1;
+    }
+
+    viewer_display(view_area.buffer, view_area.start, _file_remaining_size());
+
+    return view_area.fd;
+}
+
+void file_exit()
+{
+    close(view_area.fd);
+}
+
+/**
+ * file_paste_char pastes and flush updates to disk.
+ */
+int file_paste_char(char c, int offset)
+{
+    view_area.was_changed = 1;
+    view_area.data_len++;
+
+    memmove(view_area.buffer + offset + 1, view_area.buffer + offset, view_area.data_len - offset - 1);
+    view_area.buffer[offset] = c;
+    viewer_cursor_next();
+    viewer_display(view_area.buffer, view_area.start, _file_remaining_size());
+}
+
+/**
+ * file_paste_char pastes and flush updates to disk.
+ */
+int file_save()
+{
+    if (view_area.was_changed) {
+        _file_buf_flush();
+    }
+}
+
+/**
+ * Scroll functions update file buffer, to contain line scrolled to.
+ */
+int file_scroll_up()
+{
+    if (view_area.line == 0 || view_area.start == 0) {
+        return -1;
+    }
+    view_area.line--;
+    int old_offset_in_file = view_area.offset + view_area.start;
+    int offset_in_file = view_area.offset + view_area.start - SCREEN_X;
+    if (offset_in_file < 0) {
+        offset_in_file = 0;
+    }
+
+    if (offset_in_file >= view_area.offset) {
+        view_area.start = offset_in_file - view_area.offset;
+        _file_find_start(old_offset_in_file);
+        viewer_display(view_area.buffer, view_area.start, _file_remaining_size());
+    } else {
+        _file_buf_reload(offset_in_file);
+        _file_find_start(old_offset_in_file);
+        viewer_display(view_area.buffer, view_area.start, _file_remaining_size());
+    }
+}
+
+int file_scroll_down()
+{
+    int line_size = _file_get_size_of_first_line();
+    view_area.start += line_size;
+    if (!_file_is_last_line_in_buf()) {
+        _file_buf_reload(view_area.offset + view_area.start);
+    }
+    viewer_display(view_area.buffer, view_area.start, _file_remaining_size());
+    view_area.line++;
+}