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authorMiles Bader <miles@gnu.org>1996-07-07 16:49:06 +0000
committerMiles Bader <miles@gnu.org>1996-07-07 16:49:06 +0000
commitdd411cc7bc2ffdd07364c2abf0a4ea13cd26d79d (patch)
treedcb87c2b1322e4c83d5d4bfdcdf3fdce4fa0f445 /stdio
parent4c3e8a9e89ae7bffc7ef1cd8446b51149f4977d1 (diff)
downloadglibc-dd411cc7bc2ffdd07364c2abf0a4ea13cd26d79d.tar.gz
(lwupdate): New function, mostly was __line_wrap_update. Use POINT_COL field instead of POINT. Update D->point_offs when done. Use memmove instead of memcpy where overlap is possible (not necessary using current implementation of memcpy, but...). (__line_wrap_output): Use lwupdate. (__line_wrap_update): New function. (line_wrap_set_lmargin, line_wrap_set_rmargin, line_wrap_set_wmargin, line_wrap_point): Use __line_wrap_update. (ensure_unwrapped, ensure_wrapped): New functions.
Diffstat (limited to 'stdio')
-rw-r--r--stdio/linewrap.c176
1 files changed, 122 insertions, 54 deletions
diff --git a/stdio/linewrap.c b/stdio/linewrap.c
index 7f6576f29b..e22640da0f 100644
--- a/stdio/linewrap.c
+++ b/stdio/linewrap.c
@@ -50,6 +50,32 @@ unwrap_stream (FILE *stream, struct line_wrap_data *d)
stream->__io_funcs.__fileno = d->fileno;
stream->__io_funcs.__seek = d->seek;
}
+
+/* If WRAPPER_COOKIE points to a 0 pointer, then STREAM is assumed to be
+ wrapped, and will be unwrapped, storing the wrapper cookie into
+ WRAPPER_COOKIE. Otherwise, nothing is done. */
+static inline void
+ensure_unwrapped (FILE *stream, struct line_wrap_data **wrapper_cookie)
+{
+ if (*wrapper_cookie == 0)
+ {
+ *wrapper_cookie = stream->__cookie;
+ unwrap_stream (stream, *wrapper_cookie);
+ }
+}
+
+/* If WRAPPER_COOKIE points to a non-0 pointer, then STREAM is assumed to
+ *have been unwrapped with ensure_unwrapped, will be wrapped with
+ *WRAPPER_COOKIE, and *WRAPPER_COOKIE zeroed. Otherwise, nothing is done. */
+static inline void
+ensure_wrapped (FILE *stream, struct line_wrap_data **wrapper_cookie)
+{
+ if (*wrapper_cookie)
+ {
+ wrap_stream (stream, *wrapper_cookie);
+ *wrapper_cookie = 0;
+ }
+}
/* Cookie io functions that might get called on a wrapped stream.
Must pass the original cookie to the original functions. */
@@ -68,26 +94,26 @@ lwfileno (void *cookie)
return (*d->fileno) (d->cookie);
}
-/* This function is called when STREAM must be flushed.
- C is EOF or a character to be appended to the buffer contents. */
-void
-__line_wrap_output (FILE *stream, int c)
+/* Process STREAM's buffer so that line wrapping is done from POINT_OFFS to
+ the end of its buffer. If WRAPPER_COOKIE is 0, and it's necessary to
+ flush some data, STREAM is unwrapped, and the line wrap stdio cookie
+ stored in WRAPPER_COOKIE; otherwise, stream is assumed to already be
+ unwrapped, and WRAPPER_COOKIE to point to the line wrap data. Returns C
+ or EOF if C was output. */
+static inline int
+lwupdate (FILE *stream, int c, struct line_wrap_data **wrapper_cookie)
{
char *buf, *nl;
size_t len;
-
- /* Extract our data and restore the stream's original cookie
- and output function so writes we do really go out. */
- struct line_wrap_data *d = stream->__cookie;
- unwrap_stream (stream, d);
+ struct line_wrap_data *d = *wrapper_cookie ?: stream->__cookie;
/* Scan the buffer for newlines. */
- buf = stream->__buffer;
+ buf = stream->__buffer + d->point_offs;
while ((buf < stream->__bufp || (c != EOF && c != '\n')) && !stream->__error)
{
size_t r;
- if (d->point == 0 && d->lmargin != 0)
+ if (d->point_col == 0 && d->lmargin != 0)
{
/* We are starting a new line. Print spaces to the left margin. */
const size_t pad = d->lmargin;
@@ -106,16 +132,18 @@ __line_wrap_output (FILE *stream, int c)
size_t i;
char *olimit;
+ ensure_unwrapped (stream, wrapper_cookie);
+
len = stream->__bufp - buf;
olimit = stream->__put_limit;
stream->__bufp = stream->__put_limit = buf;
for (i = 0; i < pad; ++i)
(*d->output) (stream, ' ');
stream->__put_limit = olimit;
- memcpy (stream->__bufp, buf, len);
+ memmove (stream->__bufp, buf, len);
stream->__bufp += len;
}
- d->point = pad;
+ d->point_col = pad;
}
len = stream->__bufp - buf;
@@ -125,12 +153,12 @@ __line_wrap_output (FILE *stream, int c)
{
/* The buffer ends in a partial line. */
- if (d->point + len + (c != EOF && c != '\n') <= d->rmargin)
+ if (d->point_col + len + (c != EOF && c != '\n') <= d->rmargin)
{
/* The remaining buffer text is a partial line and fits
within the maximum line width. Advance point for the
characters to be written and stop scanning. */
- d->point += len;
+ d->point_col += len;
break;
}
else
@@ -138,11 +166,11 @@ __line_wrap_output (FILE *stream, int c)
the end of the buffer. */
nl = stream->__bufp;
}
- else if (d->point + (nl - buf) <= d->rmargin)
+ else if (d->point_col + (nl - buf) <= d->rmargin)
{
/* The buffer contains a full line that fits within the maximum
line width. Reset point and scan the next line. */
- d->point = 0;
+ d->point_col = 0;
buf = nl + 1;
continue;
}
@@ -156,10 +184,10 @@ __line_wrap_output (FILE *stream, int c)
newline and anything after it in the buffer. */
if (nl < stream->__bufp)
{
- memcpy (buf + (r - d->point), nl, stream->__bufp - nl);
- stream->__bufp -= buf + (r - d->point) - nl;
+ memmove (buf + (r - d->point_col), nl, stream->__bufp - nl);
+ stream->__bufp -= buf + (r - d->point_col) - nl;
/* Reset point for the next line and start scanning it. */
- d->point = 0;
+ d->point_col = 0;
buf += r + 1; /* Skip full line plus \n. */
}
else
@@ -167,8 +195,8 @@ __line_wrap_output (FILE *stream, int c)
/* The buffer ends with a partial line that is beyond the
maximum line width. Advance point for the characters
written, and discard those past the max from the buffer. */
- d->point += len;
- stream->__bufp -= d->point - r;
+ d->point_col += len;
+ stream->__bufp -= d->point_col - r;
if (c != '\n')
/* Swallow the extra character too. */
c = EOF;
@@ -184,7 +212,7 @@ __line_wrap_output (FILE *stream, int c)
char *p, *nextline;
int i;
- p = buf + (r + 1 - d->point);
+ p = buf + (r + 1 - d->point_col);
while (p >= buf && !isblank (*p))
--p;
nextline = p + 1; /* This will begin the next line. */
@@ -201,7 +229,7 @@ __line_wrap_output (FILE *stream, int c)
{
/* A single word that is greater than the maximum line width.
Oh well. Put it on an overlong line by itself. */
- p = buf + (r + 1 - d->point);
+ p = buf + (r + 1 - d->point_col);
/* Find the end of the long word. */
do
++p;
@@ -209,7 +237,7 @@ __line_wrap_output (FILE *stream, int c)
if (p == nl)
{
/* It already ends a line. No fussing required. */
- d->point = 0;
+ d->point_col = 0;
buf = nl + 1;
continue;
}
@@ -228,14 +256,17 @@ __line_wrap_output (FILE *stream, int c)
if (nextline - (nl + 1) < d->wmargin)
/* The margin needs more blanks than we removed.
Output the first line so we can use the space. */
- (*d->output) (stream, '\n');
+ {
+ ensure_unwrapped (stream, wrapper_cookie);
+ (*d->output) (stream, '\n');
+ }
else
/* We can fit the newline and blanks in before
the next word. */
*stream->__bufp++ = '\n';
/* Reset the counter of what has been output this line. */
- d->point = 0;
+ d->point_col = 0;
/* Add blanks up to the wrap margin column. */
for (i = 0; i < d->wmargin; ++i)
@@ -244,7 +275,7 @@ __line_wrap_output (FILE *stream, int c)
/* Copy the tail of the original buffer into the current buffer
position. */
if (stream->__bufp != nextline)
- memcpy (stream->__bufp, nextline, buf + len - nextline);
+ memmove (stream->__bufp, nextline, buf + len - nextline);
len -= nextline - buf;
/* Continue the scan on the remaining lines in the buffer. */
@@ -255,16 +286,33 @@ __line_wrap_output (FILE *stream, int c)
}
}
+ /* Remember that we've scanned as far as the end of the buffer. */
+ d->point_offs = stream->__bufp - stream->__buffer;
+
+ return c;
+}
+
+/* This function is called when STREAM must be flushed.
+ C is EOF or a character to be appended to the buffer contents. */
+void
+__line_wrap_output (FILE *stream, int c)
+{
+ struct line_wrap_data *d = 0;
+
+ c = lwupdate (stream, c, &d);
+
if (!stream->__error)
{
+ ensure_unwrapped (stream, &d);
(*d->output) (stream, c);
+ d->point_offs = 0; /* The buffer now holds nothing. */
if (c == '\n')
- d->point = 0;
+ d->point_col = 0;
else if (c != EOF)
- ++d->point;
+ ++d->point_col;
}
- wrap_stream (stream, d);
+ ensure_wrapped (stream, &d);
}
/* Modify STREAM so that it prefixes lines written on it with LMARGIN spaces
@@ -285,7 +333,8 @@ line_wrap_stream (FILE *stream, size_t lmargin, size_t rmargin, size_t wmargin)
fflush (stream);
/* Initialize our wrapping state. */
- d->point = 0;
+ d->point_col = 0;
+ d->point_offs = 0;
/* Save the original cookie and output and close hooks. */
d->cookie = stream->__cookie;
@@ -326,8 +375,28 @@ line_wrapped (FILE *stream)
return (stream->__room_funcs.__output == &__line_wrap_output);
}
+/* If STREAM is not line-wrapped, return 0. Otherwise all pending text
+ buffered text in STREAM so that the POINT_OFFS field refers to the last
+ position in the stdio buffer, and return the line wrap state object for
+ STREAM. Since all text has been processed, this means that (1) the
+ POINT_COL field refers to the column at which any new text would be added,
+ and (2) any changes to the margin parameters will only affect new text. */
+struct line_wrap_data *
+__line_wrap_update (FILE *stream)
+{
+ if (line_wrapped (stream))
+ {
+ struct line_wrap_data *d = stream->__cookie, *wc = 0;
+ lwupdate (stream, EOF, &wc);
+ ensure_wrapped (stream, &wc);
+ return d;
+ }
+ else
+ return 0;
+}
+
/* If STREAM is not line-wrapped return -1, else return its left margin. */
-size_t
+inline size_t
line_wrap_lmargin (FILE *stream)
{
if (! line_wrapped (stream))
@@ -337,22 +406,22 @@ line_wrap_lmargin (FILE *stream)
/* If STREAM is not line-wrapped return -1, else set its left margin to
LMARGIN and return the old value. */
-size_t
+inline size_t
line_wrap_set_lmargin (FILE *stream, size_t lmargin)
{
- if (! line_wrapped (stream))
- return -1;
- else
+ struct line_wrap_data *d = __line_wrap_update (stream);
+ if (d)
{
- struct line_wrap_data *d = stream->__cookie;
size_t old = d->lmargin;
d->lmargin = lmargin;
return old;
}
+ else
+ return -1;
}
/* If STREAM is not line-wrapped return -1, else return its left margin. */
-size_t
+inline size_t
line_wrap_rmargin (FILE *stream)
{
if (! line_wrapped (stream))
@@ -362,22 +431,22 @@ line_wrap_rmargin (FILE *stream)
/* If STREAM is not line-wrapped return -1, else set its right margin to
RMARGIN and return the old value. */
-size_t
+inline size_t
line_wrap_set_rmargin (FILE *stream, size_t rmargin)
{
- if (! line_wrapped (stream))
- return -1;
- else
+ struct line_wrap_data *d = __line_wrap_update (stream);
+ if (d)
{
- struct line_wrap_data *d = stream->__cookie;
size_t old = d->rmargin;
d->rmargin = rmargin;
return old;
}
+ else
+ return -1;
}
/* If STREAM is not line-wrapped return -1, else return its wrap margin. */
-size_t
+inline size_t
line_wrap_wmargin (FILE *stream)
{
if (! line_wrapped (stream))
@@ -387,28 +456,27 @@ line_wrap_wmargin (FILE *stream)
/* If STREAM is not line-wrapped return -1, else set its left margin to
WMARGIN and return the old value. */
-size_t
+inline size_t
line_wrap_set_wmargin (FILE *stream, size_t wmargin)
{
- if (! line_wrapped (stream))
- return -1;
- else
+ struct line_wrap_data *d = __line_wrap_update (stream);
+ if (d)
{
- struct line_wrap_data *d = stream->__cookie;
size_t old = d->wmargin;
d->wmargin = wmargin;
return old;
}
+ else
+ return -1;
}
/* If STREAM is not line-wrapped return -1, else return the column number of
the current output point. */
-size_t
+inline size_t
line_wrap_point (FILE *stream)
{
- if (! line_wrapped (stream))
- return -1;
- return ((struct line_wrap_data *)stream->__cookie)->point;
+ struct line_wrap_data *d = __line_wrap_update (stream);
+ return d ? d->point_col : -1;
}
#ifdef TEST