/*
* Analogous to back_line(), but deals with "raw lines".
* {{ This is supposed to be more efficient than back_line(). }}
*/
off_t
back_raw_line(off_t curr_pos, char **linep, int *line_lenp)
{
int n;
int c;
off_t new_pos;
if (curr_pos == -1 || curr_pos <= ch_zero() || ch_seek(curr_pos - 1))
return (-1);
n = size_linebuf;
linebuf[--n] = '\0';
for (;;) {
c = ch_back_get();
if (c == '\n' || ABORT_SIGS()) {
/*
* This is the newline ending the previous line.
* We have hit the beginning of the line.
*/
new_pos = ch_tell() + 1;
break;
}
if (c == EOI) {
/*
* We have hit the beginning of the file.
* This must be the first line in the file.
* This must, of course, be the beginning of the line.
*/
new_pos = ch_zero();
break;
}
if (n <= 0) {
int old_size_linebuf = size_linebuf;
char *fm;
char *to;
if (expand_linebuf()) {
/*
* Overflowed the input buffer.
* Pretend the line ended here.
*/
new_pos = ch_tell() + 1;
break;
}
/*
* Shift the data to the end of the new linebuf.
*/
for (fm = linebuf + old_size_linebuf - 1,
to = linebuf + size_linebuf - 1;
fm >= linebuf; fm--, to--)
*to = *fm;
n = size_linebuf - old_size_linebuf;
}
linebuf[--n] = c;
}
if (linep != NULL)
*linep = &linebuf[n];
if (line_lenp != NULL)
*line_lenp = size_linebuf - 1 - n;
return (new_pos);
}
/*
* Make sure the screen is displayed.
*/
static void
make_display(void)
{
/*
* If nothing is displayed yet, display starting from initial_scrpos.
*/
if (empty_screen()) {
if (initial_scrpos.pos == -1)
/*
* {{ Maybe this should be:
* jump_loc(ch_zero(), jump_sline);
* but this behavior seems rather unexpected
* on the first screen. }}
*/
jump_loc(ch_zero(), 1);
else
jump_loc(initial_scrpos.pos, initial_scrpos.ln);
} else if (screen_trashed) {
int save_top_scroll = top_scroll;
int save_ignore_eoi = ignore_eoi;
top_scroll = 1;
ignore_eoi = 0;
if (screen_trashed == 2) {
/*
* Special case used by ignore_eoi: re-open the input
* file and jump to the end of the file.
*/
reopen_curr_ifile();
jump_forw();
}
repaint();
top_scroll = save_top_scroll;
ignore_eoi = save_ignore_eoi;
}
}
/*
* Get the mark structure identified by a character.
* The mark struct may come either from the mark table
* or may be constructed on the fly for certain characters like ^, $.
*/
static struct mark *
getmark(int c)
{
register struct mark *m;
static struct mark sm;
switch (c) {
case '^':
/*
* Beginning of the current file.
*/
m = &sm;
m->m_scrpos.pos = ch_zero();
m->m_scrpos.ln = 0;
m->m_ifile = curr_ifile;
break;
case '$':
/*
* End of the current file.
*/
if (ch_end_seek()) {
error("Cannot seek to end of file", NULL_PARG);
return (NULL);
}
m = &sm;
m->m_scrpos.pos = ch_tell();
m->m_scrpos.ln = sc_height-1;
m->m_ifile = curr_ifile;
break;
case '.':
/*
* Current position in the current file.
*/
m = &sm;
get_scrpos(&m->m_scrpos);
m->m_ifile = curr_ifile;
break;
case '\'':
/*
* The "last mark".
*/
m = &marks[LASTMARK];
break;
default:
/*
* Must be a user-defined mark.
*/
m = getumark(c);
if (m == NULL)
break;
if (m->m_scrpos.pos == -1) {
error("Mark not set", NULL_PARG);
return (NULL);
}
break;
}
return (m);
}
/*
* Go to a mark.
*/
void
gomark(int c)
{
struct mark *m;
struct scrpos scrpos;
m = getmark(c);
if (m == NULL)
return;
/*
* If we're trying to go to the lastmark and
* it has not been set to anything yet,
* set it to the beginning of the current file.
*/
if (m == &marks[LASTMARK] && m->m_scrpos.pos == -1) {
m->m_ifile = curr_ifile;
m->m_scrpos.pos = ch_zero();
m->m_scrpos.ln = jump_sline;
}
/*
* If we're using lmark, we must save the screen position now,
* because if we call edit_ifile() below, lmark will change.
* (We save the screen position even if we're not using lmark.)
*/
scrpos = m->m_scrpos;
if (m->m_ifile != curr_ifile) {
/*
* Not in the current file; edit the correct file.
*/
if (edit_ifile(m->m_ifile))
return;
}
jump_loc(scrpos.pos, scrpos.ln);
}
/*
* Decode a "percent" prototype character.
* A prototype string may include various "percent" escapes;
* that is, a percent sign followed by a single letter.
* Here we decode that letter and take the appropriate action,
* usually by appending something to the message being built.
*/
static void
protochar(int c, int where)
{
off_t pos;
off_t len;
int n;
off_t linenum;
off_t last_linenum;
IFILE h;
#undef PAGE_NUM
#define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - 1)) + 1)
switch (c) {
case 'b': /* Current byte offset */
pos = curr_byte(where);
if (pos != -1)
ap_pos(pos);
else
ap_quest();
break;
case 'c':
ap_int(hshift);
break;
case 'd': /* Current page number */
linenum = currline(where);
if (linenum > 0 && sc_height > 1)
ap_pos(PAGE_NUM(linenum));
else
ap_quest();
break;
case 'D': /* Final page number */
/* Find the page number of the last byte in the file (len-1). */
len = ch_length();
if (len == -1) {
ap_quest();
} else if (len == 0) {
/* An empty file has no pages. */
ap_pos(0);
} else {
linenum = find_linenum(len - 1);
if (linenum <= 0)
ap_quest();
else
ap_pos(PAGE_NUM(linenum));
}
break;
case 'E': /* Editor name */
ap_str(editor);
break;
case 'f': /* File name */
ap_str(get_filename(curr_ifile));
break;
case 'F': /* Last component of file name */
ap_str(last_component(get_filename(curr_ifile)));
break;
case 'i': /* Index into list of files */
if (ntags())
ap_int(curr_tag());
else
ap_int(get_index(curr_ifile));
break;
case 'l': /* Current line number */
linenum = currline(where);
if (linenum != 0)
ap_pos(linenum);
else
ap_quest();
break;
case 'L': /* Final line number */
len = ch_length();
if (len == -1 || len == ch_zero() ||
(linenum = find_linenum(len)) <= 0)
ap_quest();
else
ap_pos(linenum-1);
break;
case 'm': /* Number of files */
n = ntags();
if (n)
ap_int(n);
else
ap_int(nifile());
break;
case 'p': /* Percent into file (bytes) */
pos = curr_byte(where);
len = ch_length();
if (pos != -1 && len > 0)
ap_int(percentage(pos, len));
else
ap_quest();
break;
case 'P': /* Percent into file (lines) */
linenum = currline(where);
if (linenum == 0 ||
(len = ch_length()) == -1 || len == ch_zero() ||
(last_linenum = find_linenum(len)) <= 0)
ap_quest();
else
ap_int(percentage(linenum, last_linenum));
break;
case 's': /* Size of file */
case 'B':
len = ch_length();
if (len != -1)
ap_pos(len);
else
ap_quest();
break;
case 't': /* Truncate trailing spaces in the message */
while (mp > message && mp[-1] == ' ')
mp--;
*mp = '\0';
break;
case 'T': /* Type of list */
if (ntags())
ap_str("tag");
else
ap_str("file");
break;
case 'x': /* Name of next file */
h = next_ifile(curr_ifile);
if (h != NULL)
ap_str(get_filename(h));
else
ap_quest();
break;
}
}
