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Diffstat (limited to 'libio/strops.c')
| -rw-r--r-- | libio/strops.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/libio/strops.c b/libio/strops.c new file mode 100644 index 0000000..f4f4525 --- /dev/null +++ b/libio/strops.c @@ -0,0 +1,285 @@ +/* +Copyright (C) 1993 Free Software Foundation + +This file is part of the GNU IO Library. This library is free +software; you can redistribute it and/or modify it under the +terms of the GNU General Public License as published by the +Free Software Foundation; either version 2, 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 General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this library; see the file COPYING. If not, write to the Free +Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +As a special exception, if you link this library with files +compiled with a GNU compiler to produce an executable, this does not cause +the resulting executable to be covered by the GNU General Public License. +This exception does not however invalidate any other reasons why +the executable file might be covered by the GNU General Public License. */ + +#include "strfile.h" +#include "libioP.h" +#include <string.h> + +#define LEN(fp) (((_IO_strfile*)(fp))->_s._len) + +#ifdef TODO +/* An "unbounded buffer" is when a buffer is supplied, but with no + specified length. An example is the buffer argument to sprintf. + */ +#endif + +void +DEFUN(_IO_str_init_static, (fp, ptr, size, pstart), + _IO_FILE *fp AND char *ptr AND int size AND char *pstart) +{ + if (size == 0) + size = strlen(ptr); + else if (size < 0) + { + /* If size is negative 'the characters are assumed to + continue indefinitely.' This is kind of messy ... */ +#if 1 + int s; + size = 512; + /* Try increasing powers of 2, as long as we don't wrap around. + This can lose in pathological cases (ptr near the end + of the address space). A better solution might be to + adjust the size on underflow/overflow. FIXME. */ + for (s; s = 2*size, s > 0 && ptr + s > ptr && s < 0x4000000L; ) + size = s; + size = s; +#else + /* The following semi-portable kludge assumes that + sizeof(unsigned long) == sizeof(char*). Hence, + (unsigned long)(-1) should be the largest possible address. */ + unsigned long highest = (unsigned long)(-1); + /* Pointers are signed on some brain-damaged systems, in + which case we divide by two to get the maximum signed address. */ + if ((char*)highest < ptr) + highest >>= 1; + size = (char*)highest - ptr; +#endif + } + _IO_setb(fp, ptr, ptr+size, 0); + + fp->_IO_write_base = ptr; + fp->_IO_read_base = ptr; + fp->_IO_read_ptr = ptr; + if (pstart) + { + fp->_IO_write_ptr = pstart; + fp->_IO_write_end = ptr+size; + fp->_IO_read_end = pstart; + } + else + { + fp->_IO_write_ptr = ptr; + fp->_IO_write_end = ptr; + fp->_IO_read_end = ptr+size; + } + LEN(fp) = size; + /* A null _allocate_buffer function flags the strfile as being static. */ + (((_IO_strfile*)(fp))->_s._allocate_buffer) = (_IO_alloc_type)0; +} + +void +DEFUN(_IO_str_init_readonly, (fp, ptr, size), + _IO_FILE *fp AND const char *ptr AND int size) +{ + _IO_str_init_static (fp, (char*)ptr, size, NULL); + fp->_IO_file_flags |= _IO_NO_WRITES; +} + +int +DEFUN(_IO_str_overflow, (fp, c), + register _IO_FILE* fp AND int c) +{ + int flush_only = c == EOF; + _IO_size_t pos = fp->_IO_write_ptr - fp->_IO_write_base; + _IO_size_t get_pos = fp->_IO_read_ptr - fp->_IO_read_base; + if (fp->_flags & _IO_NO_WRITES) + return flush_only ? 0 : EOF; + if (pos > LEN(fp)) LEN(fp) = pos; + if ((fp->_flags & _IO_TIED_PUT_GET) && !(fp->_flags & _IO_CURRENTLY_PUTTING)) + { + pos = get_pos; + fp->_flags |= _IO_CURRENTLY_PUTTING; + get_pos = LEN(fp); + } + if (pos >= _IO_blen(fp) + flush_only) + { + if (fp->_flags & _IO_USER_BUF) /* not allowed to enlarge */ + { +#ifdef TODO + if (indefinite size) + { + fp->_IO_buf_end += 512; + } + else +#endif + return EOF; + } + else + { + char *new_buf; + _IO_size_t new_size = 2 * _IO_blen(fp); + new_buf + = (char*)(*((_IO_strfile*)fp)->_s._allocate_buffer)(new_size); + if (new_buf == NULL) + { + /* __ferror(fp) = 1; */ + return EOF; + } + memcpy(new_buf, fp->_IO_buf_base, _IO_blen(fp)); +#if 0 + if (lenp == &LEN(fp)) /* use '\0'-filling */ + memset(new_buf + pos, 0, blen() - pos); +#endif + if (fp->_IO_buf_base) + { + (*((_IO_strfile*)fp)->_s._free_buffer)(fp->_IO_buf_base); + /* Make sure _IO_setb won't try to delete _IO_buf_base. */ + fp->_IO_buf_base = NULL; + } + _IO_setb(fp, new_buf, new_buf + new_size, 1); + fp->_IO_write_base = new_buf; + } + fp->_IO_write_end = fp->_IO_buf_end; + } + + fp->_IO_write_ptr = fp->_IO_buf_base + pos; + + fp->_IO_read_base = fp->_IO_buf_base; + fp->_IO_read_ptr = fp->_IO_buf_base + get_pos; + fp->_IO_read_end = fp->_IO_buf_base + LEN(fp); + + if (!flush_only) + *fp->_IO_write_ptr++ = (unsigned char) c; + return c; +} + +int +DEFUN(_IO_str_underflow, (fp), + register _IO_FILE* fp) +{ + _IO_size_t ppos = fp->_IO_write_ptr - fp->_IO_write_base; + if (ppos > LEN(fp)) LEN(fp) = ppos; + if ((fp->_flags & _IO_TIED_PUT_GET) && (fp->_flags & _IO_CURRENTLY_PUTTING)) + { + fp->_flags &= ~_IO_CURRENTLY_PUTTING; + fp->_IO_write_ptr = fp->_IO_write_end; + } + fp->_IO_read_end = fp->_IO_read_base + LEN(fp); + if (fp->_IO_read_ptr < fp->_IO_read_end) + return *fp->_IO_read_ptr; + else + return EOF; +} + +_IO_ssize_t +DEFUN(_IO_str_count, (fp), + register _IO_FILE *fp) +{ + _IO_ssize_t put_len = fp->_IO_write_ptr - fp->_IO_write_base; + if (put_len < LEN(fp)) + put_len = LEN(fp); + return put_len; +} + +_IO_pos_t +DEFUN(_IO_str_seekoff, (fp, offset, dir, mode), + register _IO_FILE *fp AND _IO_off_t offset AND int dir AND int mode) +{ + _IO_ssize_t cur_size = _IO_str_count(fp); + _IO_pos_t new_pos = EOF; + + /* Move the get pointer, if requested. */ + if (mode & _IOS_INPUT) + { + switch (dir) + { + case _IO_seek_end: + offset += cur_size; + break; + case _IO_seek_cur: + offset += fp->_IO_read_ptr - fp->_IO_read_base; + break; + default: /* case _IO_seek_set: */ + break; + } + if (offset < 0 || (_IO_size_t)offset > cur_size) + return EOF; + fp->_IO_read_ptr = fp->_IO_read_base + offset; + fp->_IO_read_end = fp->_IO_read_base + cur_size; + new_pos = offset; + } + + /* Move the put pointer, if requested. */ + if (mode & _IOS_OUTPUT) + { + switch (dir) + { + case _IO_seek_end: + offset += cur_size; + break; + case _IO_seek_cur: + offset += fp->_IO_write_ptr - fp->_IO_write_base; + break; + default: /* case _IO_seek_set: */ + break; + } + if (offset < 0 || (_IO_size_t)offset > cur_size) + return EOF; + LEN(fp) = cur_size; + fp->_IO_write_ptr = fp->_IO_write_base + offset; + new_pos = offset; + } + return new_pos; +} + +int +DEFUN(_IO_str_pbackfail, (fp, c), + register _IO_FILE *fp AND int c) +{ + if ((fp->_flags & _IO_NO_WRITES) && c != EOF) + return EOF; + return _IO_default_pbackfail(fp, c); +} + +void +DEFUN (_IO_str_finish, (fp), + register _IO_FILE* fp) +{ + if (fp->_IO_buf_base && !(fp->_flags & _IO_USER_BUF)) + (((_IO_strfile*)fp)->_s._free_buffer)(fp->_IO_buf_base); + fp->_IO_buf_base = NULL; + + _IO_default_finish(fp); +} + +struct _IO_jump_t _IO_str_jumps = { + JUMP_INIT_DUMMY, + JUMP_INIT(finish, _IO_str_finish), + JUMP_INIT(overflow, _IO_str_overflow), + JUMP_INIT(underflow, _IO_str_underflow), + JUMP_INIT(uflow, _IO_default_uflow), + JUMP_INIT(pbackfail, _IO_str_pbackfail), + JUMP_INIT(xsputn, _IO_default_xsputn), + JUMP_INIT(xsgetn, _IO_default_xsgetn), + JUMP_INIT(seekoff, _IO_str_seekoff), + JUMP_INIT(seekpos, _IO_default_seekpos), + JUMP_INIT(setbuf, _IO_default_setbuf), + JUMP_INIT(sync, _IO_default_sync), + JUMP_INIT(doallocate, _IO_default_doallocate), + JUMP_INIT(read, _IO_default_read), + JUMP_INIT(write, _IO_default_write), + JUMP_INIT(seek, _IO_default_seek), + JUMP_INIT(close, _IO_default_close), + JUMP_INIT(stat, _IO_default_stat) +}; |