diff options
Diffstat (limited to 'libio/readline.c')
| -rw-r--r-- | libio/readline.c | 170 |
1 files changed, 0 insertions, 170 deletions
diff --git a/libio/readline.c b/libio/readline.c deleted file mode 100644 index 99fecc5825..0000000000 --- a/libio/readline.c +++ /dev/null @@ -1,170 +0,0 @@ -/* fgets with ERANGE error reporting and size_t buffer length. - Copyright (C) 2018-2020 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <https://www.gnu.org/licenses/>. */ - -#include <assert.h> -#include <errno.h> -#include <stdio.h> -#include <string.h> - -#include "libioP.h" - -/* Return -1 and set errno to EINVAL if it is ERANGE. */ -static ssize_t -fail_no_erange (void) -{ - if (errno == ERANGE) - __set_errno (EINVAL); - return -1; -} - -/* Slow path for reading the line. Called with no data in the stream - read buffer. Write data to [BUFFER, BUFFER_END). */ -static ssize_t -readline_slow (FILE *fp, char *buffer, char *buffer_end) -{ - char *start = buffer; - - while (buffer < buffer_end) - { - if (__underflow (fp) == EOF) - { - if (_IO_ferror_unlocked (fp)) - /* If the EOF was caused by a read error, report it. */ - return fail_no_erange (); - *buffer = '\0'; - /* Do not include the null terminator. */ - return buffer - start; - } - - /* __underflow has filled the buffer. */ - char *readptr = fp->_IO_read_ptr; - ssize_t readlen = fp->_IO_read_end - readptr; - /* Make sure that __underflow really has acquired some data. */ - assert (readlen > 0); - char *pnl = memchr (readptr, '\n', readlen); - if (pnl != NULL) - { - /* We found the terminator. */ - size_t line_length = pnl - readptr; - if (line_length + 2 > buffer_end - buffer) - /* Not enough room in the caller-supplied buffer. */ - break; - memcpy (buffer, readptr, line_length + 1); - buffer[line_length + 1] = '\0'; - fp->_IO_read_ptr = pnl + 1; - /* Do not include the null terminator. */ - return buffer - start + line_length + 1; - } - - if (readlen >= buffer_end - buffer) - /* Not enough room in the caller-supplied buffer. */ - break; - - /* Save and consume the stream buffer. */ - memcpy (buffer, readptr, readlen); - fp->_IO_read_ptr = fp->_IO_read_end; - buffer += readlen; - } - - /* The line does not fit into the buffer. */ - __set_errno (ERANGE); - return -1; -} - -ssize_t -__libc_readline_unlocked (FILE *fp, char *buffer, size_t buffer_length) -{ - char *buffer_end = buffer + buffer_length; - - /* Orient the stream. */ - if (__builtin_expect (fp->_mode, -1) == 0) - _IO_fwide (fp, -1); - - /* Fast path: The line terminator is found in the buffer. */ - char *readptr = fp->_IO_read_ptr; - ssize_t readlen = fp->_IO_read_end - readptr; - off64_t start_offset; /* File offset before reading anything. */ - if (readlen > 0) - { - char *pnl = memchr (readptr, '\n', readlen); - if (pnl != NULL) - { - size_t line_length = pnl - readptr; - /* Account for line and null terminators. */ - if (line_length + 2 > buffer_length) - { - __set_errno (ERANGE); - return -1; - } - memcpy (buffer, readptr, line_length + 1); - buffer[line_length + 1] = '\0'; - /* Consume the entire line. */ - fp->_IO_read_ptr = pnl + 1; - return line_length + 1; - } - - /* If the buffer does not have enough space for what is pending - in the stream (plus a NUL terminator), the buffer is too - small. */ - if (readlen + 1 > buffer_length) - { - __set_errno (ERANGE); - return -1; - } - - /* End of line not found. We need all the buffered data. Fall - through to the slow path. */ - memcpy (buffer, readptr, readlen); - buffer += readlen; - /* The original length is invalid after this point. Use - buffer_end instead. */ -#pragma GCC poison buffer_length - /* Read the old offset before updating the read pointer. */ - start_offset = __ftello64 (fp); - fp->_IO_read_ptr = fp->_IO_read_end; - } - else - { - readlen = 0; - start_offset = __ftello64 (fp); - } - - /* Slow path: Read more data from the underlying file. We need to - restore the file pointer if the buffer is too small. First, - check if the __ftello64 call above failed. */ - if (start_offset < 0) - return fail_no_erange (); - - ssize_t result = readline_slow (fp, buffer, buffer_end); - if (result < 0) - { - if (errno == ERANGE) - { - /* Restore the file pointer so that the caller may read the - same line again. */ - if (__fseeko64 (fp, start_offset, SEEK_SET) < 0) - return fail_no_erange (); - __set_errno (ERANGE); - } - /* Do not restore the file position on other errors; it is - likely that the __fseeko64 call would fail, too. */ - return -1; - } - return readlen + result; -} -libc_hidden_def (__libc_readline_unlocked) |