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#include "../lib/container/container.h"
#include "../lib/io/io.h"
#include "../lib/aec/aec.h"
#include "../lib/tctl/tctl.h"
#include "../lib/cstr/cstr.h"
#define BUFFER_SIZE 128
char buf[BUFFER_SIZE];
container_t *string;
u64 scroll = 0;
u64 maxscroll = 0;
u64 num_lines = 0;
termios_t original;
termios_t current;
void scroll_delta(int d)
{
scroll += d;
if ((i64)(scroll) < 0) {
scroll = 0;
} else if (scroll > maxscroll) {
scroll = maxscroll;
}
}
void draw_screen()
{
window_size_t ws = tctl_get_window_size();
clear_screen();
move_cursor(0, 0);
substr_t line = getline(string->data, scroll);
for (int i = 0; i < ws.height - 1 && line.begin; ++i) {
write(STDOUT_FD, line.begin, line.end - line.begin + 1);
line = nextline(line);
}
move_cursor(0, ws.height);
wstdf("%S Line: %i/%i %S", SGR_REVERSE, scroll + 1, num_lines, SGR_REVERSE_OFF);
flush(STDOUT_FD);
}
int main(int argc, const char **argv)
{
if (argc != 1) {
wf(STDERR_FD, "pager\n");
return -1;
}
if (!isatty()) {
wf(STDERR_FD, "error: stdout is no tty! exiting.\n");
return -1;
}
string = new_container(sizeof(char));
u64 size;
while ((size = rstd(buf, BUFFER_SIZE))) {
container_append(string, buf, size);
}
container_push(string, 0);
tcgetattr(STDOUT_FD, &original);
current = original;
setcanonical(¤t, 0);
setecho(¤t, 0);
cursor_enabled(0);
tcsetattr(STDOUT_FD, ¤t);
char key;
int running = 1;
window_size_t ws = tctl_get_window_size();
num_lines = number_of_lines(string->data);
maxscroll = num_lines < ws.height ? 0 : num_lines - ws.height + 1;
draw_screen();
while (running && read(STDERR_FD, &key, 1) == 1) {
switch (key) {
case 'j': scroll_delta(1); break;
case 'k': scroll_delta(-1); break;
case 'g': scroll = 0; break;
case 'G': scroll = maxscroll; break;
case 'q':
case '\033': running = 0; break;
}
draw_screen();
}
tcsetattr(STDOUT_FD, &original);
cursor_enabled(1);
clear_screen();
move_cursor(0, 0);
return 0;
}
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