1 files changed, 307 insertions, 0 deletions
diff --git a/gnu/lib/libg++/iostream/parsestream.C b/gnu/lib/libg++/iostream/parsestream.C
new file mode 100644
index 00000000000..49135da7709
--- /dev/null
+++ b/gnu/lib/libg++/iostream/parsestream.C
@@ -0,0 +1,307 @@
+//    This is part of the iostream library, providing input/output for C++.
+//    Copyright (C) 1991 Per Bothner.
+//
+//    This library is free software; you can redistribute it and/or
+//    modify it under the terms of the GNU Library General Public
+//    License as published by the Free Software Foundation; either
+//    version 2 of the License, or (at your option) any later version.
+//
+//    This library is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+//    Library General Public License for more details.
+//
+//    You should have received a copy of the GNU Library General Public
+//    License along with this library; if not, write to the Free
+//    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+#ifdef __GNUG__
+#pragma implementation
+#endif
+#include "ioprivate.h"
+#include "parsestream.h"
+
+streambuf* parsebuf::setbuf(char*, int)
+{
+    return NULL;
+}
+
+int parsebuf::tell_in_line()
+{
+    return 0;
+}
+
+int parsebuf::pbackfail(int c)
+{
+    if (c == EOF)
+	return 0;
+    if (seekoff(-1, ios::cur) == EOF)
+	return EOF;
+    return (unsigned char)c;
+}
+
+char* parsebuf::current_line() { return NULL; }
+
+streampos parsebuf::seekoff(streamoff offset, _seek_dir dir, int)
+{
+    // Make offset relative to line start.
+    switch (dir) {
+      case ios::beg:
+	offset -= pos_at_line_start;
+	break;
+      case ios::cur:
+	offset += tell_in_line();
+	break;
+      default:
+	return EOF;
+    }
+    if (offset < -1)
+	return EOF;
+    if (offset > _line_length + 1)
+	return EOF;
+    return seek_in_line(offset) + pos_at_line_start;
+}
+
+// string_parsebuf invariants:
+// The reserve ares (base() .. ebuf()) is always the entire string.
+// The get area (eback() .. egptr()) is the extended current line
+// (i.e. with the '\n' at either end, if these exist).
+
+string_parsebuf::string_parsebuf(char *buf, int len,
+				 int delete_at_close /* = 0*/)
+: parsebuf()
+{
+    setb(buf, buf+len, delete_at_close);
+    register char *ptr = buf;
+    while (ptr < ebuf() && *ptr != '\n') ptr++;
+    _line_length = ptr - buf;
+    setg(buf, buf, ptr);
+}
+
+int string_parsebuf::underflow()
+{
+    register char* ptr = egptr(); // Point to end of current_line
+    do {
+	int i = right() - ptr;
+	if (i <= 0)
+	    return EOF;
+	ptr++; i--; // Skip '\n'.
+	char *line_start = ptr;
+	while (ptr < right() && *ptr == '\n') ptr++;
+	setg(line_start-1, line_start, ptr + (ptr < right()));
+	pos_at_line_start = line_start - left();
+	_line_length = ptr - line_start;
+	__line_number++;
+    } while (gptr() == ptr);
+    return *gptr();
+}
+
+char* string_parsebuf::current_line()
+{
+    char *ptr = eback();
+    if (__line_number > 0)
+	ptr++; // Skip '\n' at end of previous line.
+    return ptr;
+}
+
+int string_parsebuf::tell_in_line()
+{
+    int offset = gptr() - eback();
+    if (__line_number > 0)
+	offset--;
+    return offset;
+}
+
+int string_parsebuf::seek_in_line(int i)
+{
+    int delta = i - tell_in_line();
+    gbump(delta); // FIXME: Needs error (bounds) checking!
+    return i;
+}
+
+static const char NewLine[1] = { '\n' };
+
+general_parsebuf::general_parsebuf(streambuf *buf, int delete_arg_buf)
+ : parsebuf()
+{
+    delete_buf = delete_arg_buf;
+    sbuf = buf;
+    int buf_size = 128;
+    char* buffer = ALLOC_BUF(buf_size);
+    setb(buffer, buffer+buf_size, 1);
+//    setg(buffer, buffer, buffer);
+}
+
+general_parsebuf::~general_parsebuf()
+{
+    if (delete_buf)
+	delete sbuf;
+}
+
+int general_parsebuf::underflow()
+{
+    register char *ptr = base();
+    int has_newline = eback() < gptr() && gptr()[-1] == '\n';
+    if (has_newline)
+	*ptr++ = '\n';
+    register streambuf *sb = sbuf;
+    register int ch;
+    for (;;) {
+	ch = sb->sbumpc();
+	if (ch == EOF)
+	    break;
+	if (ptr == ebuf()) {
+	    int old_size = ebuf() - base();
+	    char *new_buffer = new char[old_size * 2];
+	    memcpy(new_buffer, base(), old_size);
+	    setb(new_buffer, new_buffer + 2 * old_size, 1);
+	    ptr = new_buffer + old_size;
+	}
+	*ptr++ = ch;
+	if (ch == '\n')
+	    break;
+    }
+    char *cur_pos = base() + has_newline;
+    pos_at_line_start += _line_length + 1;
+    _line_length = ptr - cur_pos;
+    if (ch != EOF || _line_length > 0)
+	__line_number++;
+    setg(base(), cur_pos, ptr);
+    return ptr == cur_pos ? EOF : cur_pos[0];
+}
+
+char* general_parsebuf::current_line()
+{
+    char* ret = base();
+    if (__line_number > 1)
+	ret++; // Move past '\n' from end of previous line.
+    return ret;
+}
+
+int general_parsebuf::tell_in_line()
+{
+    int off = gptr() - base();
+    if (__line_number > 1)
+	off--; // Subtract 1 for '\n' from end of previous line.
+    return off;
+}
+
+int general_parsebuf::seek_in_line(int i)
+{
+    if (__line_number == 0)
+	(void)general_parsebuf::underflow();
+    if (__line_number > 1)
+	i++; // Add 1 for '\n' from end of previous line.
+    if (i < 0) i = 0;
+    int len = egptr() - eback();
+    if (i > len) i = len;
+    setg(base(), base() + i, egptr());
+    return i;
+}
+
+func_parsebuf::func_parsebuf(CharReader func, void *argm) : parsebuf()
+{
+    read_func = func;
+    arg = argm;
+    buf_start = NULL;
+    buf_end = NULL;
+    setb((char*)NewLine, (char*)NewLine+1, 0);
+    setg((char*)NewLine, (char*)NewLine+1, (char*)NewLine+1);
+    backed_up_to_newline = 0;
+}
+
+int func_parsebuf::tell_in_line()
+{
+    if (buf_start == NULL)
+	return 0;
+    if (egptr() != (char*)NewLine+1)
+	// Get buffer was line buffer.
+	return gptr() - buf_start;
+    if (backed_up_to_newline)
+	return -1;  // Get buffer is '\n' preceding current line.
+    // Get buffer is '\n' following current line.
+    return (buf_end - buf_start) + (gptr() - (char*)NewLine);
+}
+
+char* func_parsebuf::current_line()
+{
+    return buf_start;
+}
+
+int func_parsebuf::seek_in_line(int i)
+{
+    if (i < 0) {
+	// Back up to preceding '\n'.
+	if (i < -1) i = -1;
+	backed_up_to_newline = 1;
+	setg((char*)NewLine, (char*)NewLine+(i+1), (char*)NewLine+1);
+	return i;
+    }
+    backed_up_to_newline = 0;
+    int line_length = buf_end-buf_start;
+    if (i <= line_length) {
+	setg(buf_start, buf_start+i, buf_end);
+	return i;
+    }
+    i -= line_length;
+    if (i > 0) i = 1;
+    setg((char*)NewLine, (char*)NewLine+i, (char*)NewLine+1);
+    return line_length + i;
+}
+
+int func_parsebuf::underflow()
+{
+  retry:
+    if (gptr() < egptr())
+	return *gptr();
+    if (gptr() != (char*)NewLine+1) {
+	// Get buffer was line buffer.  Move to following '\n'.
+	setg((char*)NewLine, (char*)NewLine, (char*)NewLine+1);
+	return *gptr();
+    }
+    if (backed_up_to_newline)
+	// Get buffer was '\n' preceding current line. Move to current line.
+	backed_up_to_newline = 0;
+    else {
+	// Get buffer was '\n' following current line. Read new line.
+	if (buf_start) free(buf_start);
+	char *str = (*read_func)(arg);
+	buf_start = str;
+	if (str == NULL)
+	    return EOF;
+	// Initially, _line_length == -1, so pos_at_line_start becomes 0.
+	pos_at_line_start += _line_length + 1;
+	_line_length = strlen(str);
+	buf_end = str + _line_length;
+	__line_number++;
+    }
+    setg(buf_start, buf_start, buf_end);
+    goto retry;
+}
+
+#if 0
+size_t parsebuf::line_length()
+{
+    if (current_line_length == (size_t)(-1)) // Initial value;
+	(void)sgetc();
+    return current_line_length;
+}
+#endif
+
+int parsebuf::seek_in_line(int i)
+{
+#if 1
+    abort();
+    return 0; // Suppress warning.
+#else
+    if (i > 0) {
+	size_t len = line_length();
+	if ((unsigned)i > len) i = len;
+    }
+    else if (i < -1) i = -1;
+    int new_pos = seekoff(pos_at_line_start + i, ios::beg);
+    if (new_pos == EOF)
+	return tell_in_line();
+    else return new_pos - pos_at_line_start;
+#endif
+}