/* * Copyright (C) 1984-2012 Mark Nudelman * Modified for use with illumos by Garrett D'Amore. * Copyright 2014 Garrett D'Amore * * You may distribute under the terms of either the GNU General Public * License or the Less License, as specified in the README file. * * For more information, see the README file. */ /* * Routines to manipulate the "line buffer". * The line buffer holds a line of output as it is being built * in preparation for output to the screen. */ #include #include #include "charset.h" #include "less.h" static char *linebuf = NULL; /* Buffer which holds the current output line */ static char *attr = NULL; /* Extension of linebuf to hold attributes */ int size_linebuf = 0; /* Size of line buffer (and attr buffer) */ static int cshift; /* Current left-shift of output line buffer */ int hshift; /* Desired left-shift of output line buffer */ int tabstops[TABSTOP_MAX] = { 0 }; /* Custom tabstops */ int ntabstops = 1; /* Number of tabstops */ int tabdefault = 8; /* Default repeated tabstops */ off_t highest_hilite; /* Pos of last hilite in file found so far */ static int curr; /* Total number of bytes in linebuf */ static int column; /* Display columns needed to show linebuf */ static int overstrike; /* Next char should overstrike previous char */ static int is_null_line; /* There is no current line */ static int lmargin; /* Index in linebuf of start of content */ static char pendc; static off_t pendpos; static char *end_ansi_chars; static char *mid_ansi_chars; static int attr_swidth(int); static int attr_ewidth(int); static int do_append(LWCHAR, char *, off_t); extern int bs_mode; extern int linenums; extern int ctldisp; extern int twiddle; extern int binattr; extern int status_col; extern int auto_wrap, ignaw; extern int bo_s_width, bo_e_width; extern int ul_s_width, ul_e_width; extern int bl_s_width, bl_e_width; extern int so_s_width, so_e_width; extern int sc_width, sc_height; extern int utf_mode; extern off_t start_attnpos; extern off_t end_attnpos; static char mbc_buf[MAX_UTF_CHAR_LEN]; static int mbc_buf_index = 0; static off_t mbc_pos; /* * Initialize from environment variables. */ void init_line(void) { end_ansi_chars = lgetenv("LESSANSIENDCHARS"); if (end_ansi_chars == NULL || *end_ansi_chars == '\0') end_ansi_chars = "m"; mid_ansi_chars = lgetenv("LESSANSIMIDCHARS"); if (mid_ansi_chars == NULL || *mid_ansi_chars == '\0') mid_ansi_chars = "0123456789;[?!\"'#%()*+ "; linebuf = ecalloc(LINEBUF_SIZE, sizeof (char)); attr = ecalloc(LINEBUF_SIZE, sizeof (char)); size_linebuf = LINEBUF_SIZE; } /* * Expand the line buffer. */ static int expand_linebuf(void) { /* Double the size of the line buffer. */ int new_size = size_linebuf * 2; /* Just realloc to expand the buffer, if we can. */ char *new_buf = recallocarray(linebuf, size_linebuf, new_size, 1); char *new_attr = recallocarray(attr, size_linebuf, new_size, 1); if (new_buf == NULL || new_attr == NULL) { free(new_attr); free(new_buf); return (1); } linebuf = new_buf; attr = new_attr; size_linebuf = new_size; return (0); } /* * Is a character ASCII? */ static int is_ascii_char(LWCHAR ch) { return (ch <= 0x7F); } /* * Rewind the line buffer. */ void prewind(void) { curr = 0; column = 0; cshift = 0; overstrike = 0; is_null_line = 0; pendc = '\0'; lmargin = 0; if (status_col) lmargin += 1; } /* * Insert the line number (of the given position) into the line buffer. */ void plinenum(off_t pos) { off_t linenum = 0; int i; if (linenums == OPT_ONPLUS) { /* * Get the line number and put it in the current line. * {{ Note: since find_linenum calls forw_raw_line, * it may seek in the input file, requiring the caller * of plinenum to re-seek if necessary. }} * {{ Since forw_raw_line modifies linebuf, we must * do this first, before storing anything in linebuf. }} */ linenum = find_linenum(pos); } /* * Display a status column if the -J option is set. */ if (status_col) { linebuf[curr] = ' '; if (start_attnpos != -1 && pos >= start_attnpos && pos < end_attnpos) attr[curr] = AT_NORMAL|AT_HILITE; else attr[curr] = AT_NORMAL; curr++; column++; } /* * Display the line number at the start of each line * if the -N option is set. */ if (linenums == OPT_ONPLUS) { char buf[23]; int n; postoa(linenum, buf, sizeof(buf)); n = strlen(buf); if (n < MIN_LINENUM_WIDTH) n = MIN_LINENUM_WIDTH; snprintf(linebuf+curr, size_linebuf-curr, "%*s ", n, buf); n++; /* One space after the line number. */ for (i = 0; i < n; i++) attr[curr+i] = AT_NORMAL; curr += n; column += n; lmargin += n; } /* * Append enough spaces to bring us to the lmargin. */ while (column < lmargin) { linebuf[curr] = ' '; attr[curr++] = AT_NORMAL; column++; } } /* * Shift the input line left. * Starting at lmargin, some bytes are discarded from the linebuf, * until the number of display columns needed to show these bytes * would exceed the argument. */ static void pshift(int shift) { int shifted = 0; /* Number of display columns already discarded. */ int from; /* Index in linebuf of the current character. */ int to; /* Index in linebuf to move this character to. */ int len; /* Number of bytes in this character. */ int width = 0; /* Display columns needed for this character. */ int prev_attr; /* Attributes of the preceding character. */ int next_attr; /* Attributes of the following character. */ unsigned char c; /* First byte of current character. */ if (shift > column - lmargin) shift = column - lmargin; if (shift > curr - lmargin) shift = curr - lmargin; to = from = lmargin; /* * We keep on going when shifted == shift * to get all combining chars. */ while (shifted <= shift && from < curr) { c = linebuf[from]; if (ctldisp == OPT_ONPLUS && c == ESC) { /* Keep cumulative effect. */ linebuf[to] = c; attr[to++] = attr[from++]; while (from < curr && linebuf[from]) { linebuf[to] = linebuf[from]; attr[to++] = attr[from]; if (!is_ansi_middle(linebuf[from++])) break; } continue; } if (utf_mode && !isascii(c)) { wchar_t ch; /* * Before this point, UTF-8 validity was already * checked, but for additional safety, treat * invalid bytes as single-width characters * if they ever make it here. Similarly, treat * non-printable characters as width 1. */ len = mbtowc(&ch, linebuf + from, curr - from); if (len == -1) len = width = 1; else if ((width = wcwidth(ch)) == -1) width = 1; } else { len = 1; if (c == '\b') /* XXX - Incorrect if several '\b' in a row. */ width = width > 0 ? -width : -1; else width = iscntrl(c) ? 0 : 1; } if (width == 2 && shift - shifted == 1) { /* * Move the first half of a double-width character * off screen. Print a space instead of the second * half. This should never happen when called * by pshift_all(). */ attr[to] = attr[from]; linebuf[to++] = ' '; from += len; shifted++; break; } /* Adjust width for magic cookies. */ prev_attr = (to > 0) ? attr[to-1] : AT_NORMAL; next_attr = (from + len < curr) ? attr[from + len] : prev_attr; if (!is_at_equiv(attr[from], prev_attr) && !is_at_equiv(attr[from], next_attr)) { width += attr_swidth(attr[from]); if (from + len < curr) width += attr_ewidth(attr[from]); if (is_at_equiv(prev_attr, next_attr)) { width += attr_ewidth(prev_attr); if (from + len < curr) width += attr_swidth(next_attr); } } if (shift - shifted < width) break; from += len; shifted += width; if (shifted < 0) shifted = 0; } while (from < curr) { linebuf[to] = linebuf[from]; attr[to++] = attr[from++]; } curr = to; column -= shifted; cshift += shifted; } /* * */ void pshift_all(void) { pshift(column); } /* * Return the printing width of the start (enter) sequence * for a given character attribute. */ static int attr_swidth(int a) { int w = 0; a = apply_at_specials(a); if (a & AT_UNDERLINE) w += ul_s_width; if (a & AT_BOLD) w += bo_s_width; if (a & AT_BLINK) w += bl_s_width; if (a & AT_STANDOUT) w += so_s_width; return (w); } /* * Return the printing width of the end (exit) sequence * for a given character attribute. */ static int attr_ewidth(int a) { int w = 0; a = apply_at_specials(a); if (a & AT_UNDERLINE) w += ul_e_width; if (a & AT_BOLD) w += bo_e_width; if (a & AT_BLINK) w += bl_e_width; if (a & AT_STANDOUT) w += so_e_width; return (w); } /* * Return the printing width of a given character and attribute, * if the character were added to the current position in the line buffer. * Adding a character with a given attribute may cause an enter or exit * attribute sequence to be inserted, so this must be taken into account. */ static int pwidth(wchar_t ch, int a, wchar_t prev_ch) { int w; /* * In case of a backspace, back up by the width of the previous * character. If that is non-printable (for example another * backspace) or zero width (for example a combining accent), * the terminal may actually back up to a character even further * back, but we no longer know how wide that may have been. * The best guess possible at this point is that it was * hopefully width one. */ if (ch == L'\b') { w = wcwidth(prev_ch); if (w <= 0) w = 1; return (-w); } w = wcwidth(ch); /* * Non-printable characters can get here if the -r flag is in * effect, and possibly in some other situations (XXX check that!). * Treat them as zero width. * That may not always match their actual behaviour, * but there is no reasonable way to be more exact. */ if (w == -1) w = 0; /* * Combining accents take up no space. * Some terminals, upon failure to compose them with the * characters that precede them, will actually take up one column * for the combining accent; there isn't much we could do short * of testing the (complex) composition process ourselves and * printing a binary representation when it fails. */ if (w == 0) return (0); /* * Other characters take one or two columns, * plus the width of any attribute enter/exit sequence. */ if (curr > 0 && !is_at_equiv(attr[curr-1], a)) w += attr_ewidth(attr[curr-1]); if ((apply_at_specials(a) != AT_NORMAL) && (curr == 0 || !is_at_equiv(attr[curr-1], a))) w += attr_swidth(a); return (w); } /* * Delete to the previous base character in the line buffer. * Return 1 if one is found. */ static int backc(void) { wchar_t ch, prev_ch; int i, len, width; if ((len = mbtowc_left(&ch, linebuf + curr, curr)) <= 0) return (0); curr -= len; /* This assumes that there is no '\b' in linebuf. */ while (curr >= lmargin && column > lmargin && !(attr[curr] & (AT_ANSI|AT_BINARY))) { if ((len = mbtowc_left(&prev_ch, linebuf + curr, curr)) <= 0) prev_ch = L'\0'; width = pwidth(ch, attr[curr], prev_ch); column -= width; if (width > 0) return (1); curr -= len; if (prev_ch == L'\0') return (0); ch = prev_ch; } return (0); } /* * Is a character the end of an ANSI escape sequence? */ static int is_ansi_end(LWCHAR ch) { if (!is_ascii_char(ch)) return (0); return (strchr(end_ansi_chars, (char)ch) != NULL); } /* * */ int is_ansi_middle(LWCHAR ch) { if (!is_ascii_char(ch)) return (0); if (is_ansi_end(ch)) return (0); return (strchr(mid_ansi_chars, (char)ch) != NULL); } /* * Append a character and attribute to the line buffer. */ static int store_char(LWCHAR ch, char a, char *rep, off_t pos) { int i; int w; int replen; char cs; int matches; if (is_hilited(pos, pos+1, 0, &matches)) { /* * This character should be highlighted. * Override the attribute passed in. */ if (a != AT_ANSI) { if (highest_hilite != -1 && pos > highest_hilite) highest_hilite = pos; a |= AT_HILITE; } } w = -1; if (ctldisp == OPT_ONPLUS) { /* * Set i to the beginning of an ANSI escape sequence * that was begun and not yet ended, or to -1 otherwise. */ for (i = curr - 1; i >= 0; i--) { if (linebuf[i] == ESC) break; if (!is_ansi_middle(linebuf[i])) i = 0; } if (i >= 0 && !is_ansi_end(ch) && !is_ansi_middle(ch)) { /* Remove whole unrecognized sequence. */ curr = i; return (0); } if (i >= 0 || ch == ESC) { a = AT_ANSI; /* Will force re-AT_'ing around it. */ w = 0; } } if (w == -1) { wchar_t prev_ch; if (mbtowc_left(&prev_ch, linebuf + curr, curr) <= 0) prev_ch = L' '; w = pwidth(ch, a, prev_ch); } if (ctldisp != OPT_ON && column + w + attr_ewidth(a) > sc_width) /* * Won't fit on screen. */ return (1); if (rep == NULL) { cs = (char)ch; rep = &cs; replen = 1; } else { replen = utf_len(rep[0]); } if (curr + replen >= size_linebuf-6) { /* * Won't fit in line buffer. * Try to expand it. */ if (expand_linebuf()) return (1); } while (replen-- > 0) { linebuf[curr] = *rep++; attr[curr] = a; curr++; } column += w; return (0); } /* * Append a tab to the line buffer. * Store spaces to represent the tab. */ static int store_tab(int attr, off_t pos) { int to_tab = column + cshift - lmargin; int i; if (ntabstops < 2 || to_tab >= tabstops[ntabstops-1]) to_tab = tabdefault - ((to_tab - tabstops[ntabstops-1]) % tabdefault); else { for (i = ntabstops - 2; i >= 0; i--) if (to_tab >= tabstops[i]) break; to_tab = tabstops[i+1] - to_tab; } if (column + to_tab - 1 + pwidth(' ', attr, 0) + attr_ewidth(attr) > sc_width) return (1); do { if (store_char(' ', attr, " ", pos)) return (1); } while (--to_tab > 0); return (0); } static int store_prchar(char c, off_t pos) { char *s; /* * Convert to printable representation. */ s = prchar(c); /* * Make sure we can get the entire representation * of the character on this line. */ if (column + (int)strlen(s) - 1 + pwidth(' ', binattr, 0) + attr_ewidth(binattr) > sc_width) return (1); for (; *s != 0; s++) { if (store_char(*s, AT_BINARY, NULL, pos)) return (1); } return (0); } static int flush_mbc_buf(off_t pos) { int i; for (i = 0; i < mbc_buf_index; i++) { if (store_prchar(mbc_buf[i], pos)) return (mbc_buf_index - i); } return (0); } /* * Append a character to the line buffer. * Expand tabs into spaces, handle underlining, boldfacing, etc. * Returns 0 if ok, 1 if couldn't fit in buffer. */ int pappend(char c, off_t pos) { mbstate_t mbs; size_t sz; wchar_t ch; int r; if (pendc) { if (do_append(pendc, NULL, pendpos)) /* * Oops. We've probably lost the char which * was in pendc, since caller won't back up. */ return (1); pendc = '\0'; } if (c == '\r' && bs_mode == BS_SPECIAL) { if (mbc_buf_index > 0) /* utf_mode must be on. */ { /* Flush incomplete (truncated) sequence. */ r = flush_mbc_buf(mbc_pos); mbc_buf_index = 0; if (r) return (r + 1); } /* * Don't put the CR into the buffer until we see * the next char. If the next char is a newline, * discard the CR. */ pendc = c; pendpos = pos; return (0); } if (!utf_mode) { r = do_append((LWCHAR) c, NULL, pos); } else { for (;;) { if (mbc_buf_index == 0) mbc_pos = pos; mbc_buf[mbc_buf_index++] = c; memset(&mbs, 0, sizeof(mbs)); sz = mbrtowc(&ch, mbc_buf, mbc_buf_index, &mbs); /* Incomplete UTF-8: wait for more bytes. */ if (sz == (size_t)-2) return (0); /* Valid UTF-8: use the character. */ if (sz != (size_t)-1) { r = do_append(ch, mbc_buf, mbc_pos) ? mbc_buf_index : 0; break; } /* Invalid start byte: encode it. */ if (mbc_buf_index == 1) { r = store_prchar(c, pos); break; } /* * Invalid continuation. * Encode the preceding bytes. * If they fit, handle the interrupting byte. * Otherwise, tell the caller to back up * by the number of bytes that do not fit, * plus one for the new byte. */ mbc_buf_index--; if ((r = flush_mbc_buf(mbc_pos) + 1) == 1) mbc_buf_index = 0; else break; } } /* * If we need to shift the line, do it. * But wait until we get to at least the middle of the screen, * so shifting it doesn't affect the chars we're currently * pappending. (Bold & underline can get messed up otherwise.) */ if (cshift < hshift && column > sc_width / 2) { linebuf[curr] = '\0'; pshift(hshift - cshift); } mbc_buf_index = 0; return (r); } static int do_append(LWCHAR ch, char *rep, off_t pos) { wchar_t prev_ch; int a; a = AT_NORMAL; if (ch == '\b') { if (bs_mode == BS_CONTROL) goto do_control_char; /* * A better test is needed here so we don't * backspace over part of the printed * representation of a binary character. */ if (curr <= lmargin || column <= lmargin || (attr[curr - 1] & (AT_ANSI|AT_BINARY))) { if (store_prchar('\b', pos)) return (1); } else if (bs_mode == BS_NORMAL) { if (store_char(ch, AT_NORMAL, NULL, pos)) return (1); } else if (bs_mode == BS_SPECIAL) { overstrike = backc(); } return (0); } if (overstrike > 0) { /* * Overstrike the character at the current position * in the line buffer. This will cause either * underline (if a "_" is overstruck), * bold (if an identical character is overstruck), * or just deletion of the character in the buffer. */ overstrike = utf_mode ? -1 : 0; /* To be correct, this must be a base character. */ if (mbtowc(&prev_ch, linebuf + curr, MB_CUR_MAX) == -1) { (void)mbtowc(NULL, NULL, MB_CUR_MAX); prev_ch = L'\0'; } a = attr[curr]; if (ch == prev_ch) { /* * Overstriking a char with itself means make it bold. * But overstriking an underscore with itself is * ambiguous. It could mean make it bold, or * it could mean make it underlined. * Use the previous overstrike to resolve it. */ if (ch == '_') { if ((a & (AT_BOLD|AT_UNDERLINE)) != AT_NORMAL) a |= (AT_BOLD|AT_UNDERLINE); else if (curr > 0 && attr[curr - 1] & AT_UNDERLINE) a |= AT_UNDERLINE; else if (curr > 0 && attr[curr - 1] & AT_BOLD) a |= AT_BOLD; else a |= AT_INDET; } else { a |= AT_BOLD; } } else if (ch == '_' && prev_ch != L'\0') { a |= AT_UNDERLINE; ch = prev_ch; rep = linebuf + curr; } else if (prev_ch == '_') { a |= AT_UNDERLINE; } /* Else we replace prev_ch, but we keep its attributes. */ } else if (overstrike < 0) { if (wcwidth(ch) == 0) { /* Continuation of the same overstrike. */ if (curr > 0) a = attr[curr - 1] & (AT_UNDERLINE | AT_BOLD); else a = AT_NORMAL; } else overstrike = 0; } if (ch == '\t') { /* * Expand a tab into spaces. */ switch (bs_mode) { case BS_CONTROL: goto do_control_char; case BS_NORMAL: case BS_SPECIAL: if (store_tab(a, pos)) return (1); break; } } else if ((!utf_mode || is_ascii_char(ch)) && !isprint((unsigned char)ch)) { do_control_char: if (ctldisp == OPT_ON || (ctldisp == OPT_ONPLUS && ch == ESC)) { /* * Output as a normal character. */ if (store_char(ch, AT_NORMAL, rep, pos)) return (1); } else { if (store_prchar(ch, pos)) return (1); } } else if (utf_mode && ctldisp != OPT_ON && !iswprint(ch)) { char *s; s = prutfchar(ch); if (column + (int)strlen(s) - 1 + pwidth(' ', binattr, 0) + attr_ewidth(binattr) > sc_width) return (1); for (; *s != 0; s++) { if (store_char(*s, AT_BINARY, NULL, pos)) return (1); } } else { if (store_char(ch, a, rep, pos)) return (1); } return (0); } /* * */ int pflushmbc(void) { int r = 0; if (mbc_buf_index > 0) { /* Flush incomplete (truncated) sequence. */ r = flush_mbc_buf(mbc_pos); mbc_buf_index = 0; } return (r); } /* * Terminate the line in the line buffer. */ void pdone(int endline, int forw) { int i; (void) pflushmbc(); if (pendc && (pendc != '\r' || !endline)) /* * If we had a pending character, put it in the buffer. * But discard a pending CR if we are at end of line * (that is, discard the CR in a CR/LF sequence). */ (void) do_append(pendc, NULL, pendpos); for (i = curr - 1; i >= 0; i--) { if (attr[i] & AT_INDET) { attr[i] &= ~AT_INDET; if (i < curr - 1 && attr[i + 1] & AT_BOLD) attr[i] |= AT_BOLD; else attr[i] |= AT_UNDERLINE; } } /* * Make sure we've shifted the line, if we need to. */ if (cshift < hshift) pshift(hshift - cshift); if (ctldisp == OPT_ONPLUS && is_ansi_end('m')) { /* Switch to normal attribute at end of line. */ char *p = "\033[m"; for (; *p != '\0'; p++) { linebuf[curr] = *p; attr[curr++] = AT_ANSI; } } /* * Add a newline if necessary, * and append a '\0' to the end of the line. * We output a newline if we're not at the right edge of the screen, * or if the terminal doesn't auto wrap, * or if this is really the end of the line AND the terminal ignores * a newline at the right edge. * (In the last case we don't want to output a newline if the terminal * doesn't ignore it since that would produce an extra blank line. * But we do want to output a newline if the terminal ignores it in case * the next line is blank. In that case the single newline output for * that blank line would be ignored!) */ if (column < sc_width || !auto_wrap || (endline && ignaw) || ctldisp == OPT_ON) { linebuf[curr] = '\n'; attr[curr] = AT_NORMAL; curr++; } else if (ignaw && column >= sc_width && forw) { /* * Terminals with "ignaw" don't wrap until they *really* need * to, i.e. when the character *after* the last one to fit on a * line is output. But they are too hard to deal with when they * get in the state where a full screen width of characters * have been output but the cursor is sitting on the right edge * instead of at the start of the next line. * So we nudge them into wrapping by outputting a space * character plus a backspace. But do this only if moving * forward; if we're moving backward and drawing this line at * the top of the screen, the space would overwrite the first * char on the next line. We don't need to do this "nudge" * at the top of the screen anyway. */ linebuf[curr] = ' '; attr[curr++] = AT_NORMAL; linebuf[curr] = '\b'; attr[curr++] = AT_NORMAL; } linebuf[curr] = '\0'; attr[curr] = AT_NORMAL; } /* * */ void set_status_col(char c) { linebuf[0] = c; attr[0] = AT_NORMAL|AT_HILITE; } /* * Get a character from the current line. * Return the character as the function return value, * and the character attribute in *ap. */ int gline(int i, int *ap) { if (is_null_line) { /* * If there is no current line, we pretend the line is * either "~" or "", depending on the "twiddle" flag. */ if (twiddle) { if (i == 0) { *ap = AT_BOLD; return ('~'); } --i; } /* Make sure we're back to AT_NORMAL before the '\n'. */ *ap = AT_NORMAL; return (i ? '\0' : '\n'); } *ap = attr[i]; return (linebuf[i] & 0xFF); } /* * Indicate that there is no current line. */ void null_line(void) { is_null_line = 1; cshift = 0; } /* * Analogous to forw_line(), but deals with "raw lines": * lines which are not split for screen width. * {{ This is supposed to be more efficient than forw_line(). }} */ off_t forw_raw_line(off_t curr_pos, char **linep, int *line_lenp) { int n; int c; off_t new_pos; if (curr_pos == -1 || ch_seek(curr_pos) || (c = ch_forw_get()) == EOI) return (-1); n = 0; for (;;) { if (c == '\n' || c == EOI || abort_sigs()) { new_pos = ch_tell(); break; } if (n >= size_linebuf-1) { if (expand_linebuf()) { /* * Overflowed the input buffer. * Pretend the line ended here. */ new_pos = ch_tell() - 1; break; } } linebuf[n++] = (char)c; c = ch_forw_get(); } linebuf[n] = '\0'; if (linep != NULL) *linep = linebuf; if (line_lenp != NULL) *line_lenp = n; return (new_pos); } /* * 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; 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. */ n = size_linebuf - old_size_linebuf; memmove(linebuf + n, 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); }