/* Copyright (C) 2004 Manuel Novoa III <mjn3@codepoet.org> * * GNU Library General Public License (LGPL) version 2 or later. * * Dedicated to Toni. See uClibc/DEDICATION.mjn3 for details. */ #include "_stdio.h" libc_hidden_proto(read) libc_hidden_proto(abort) /* Given a reading stream without its end-of-file indicator set and * with no buffered input or ungots, read at most 'bufsize' bytes * into 'buf' (which may be the stream's __bufstart). * If a read error occurs, set the stream's error indicator. * If EOF is encountered, set the stream's end-of-file indicator. * * Returns the number of bytes read, even in EOF and error cases. * * Notes: * Calling with bufsize == 0 is NOT permitted (unlike __stdio_WRITE). * NOT THREADSAFE! Assumes stream already locked if necessary. */ size_t attribute_hidden __stdio_READ(register FILE *stream, unsigned char *buf, size_t bufsize) { ssize_t rv = 0; __STDIO_STREAM_VALIDATE(stream); assert(stream->__filedes >= -1); assert(__STDIO_STREAM_IS_READING(stream)); assert(!__STDIO_STREAM_BUFFER_RAVAIL(stream)); /* Buffer must be empty. */ assert(!(stream->__modeflags & __FLAG_UNGOT)); assert(bufsize); if (!__FEOF_UNLOCKED(stream)) { if (bufsize > SSIZE_MAX) { bufsize = SSIZE_MAX; } #ifdef __UCLIBC_MJN3_ONLY__ #warning EINTR? #endif /* RETRY: */ if ((rv = __READ(stream, (char *) buf, bufsize)) <= 0) { if (rv == 0) { __STDIO_STREAM_SET_EOF(stream); } else { /* if (errno == EINTR) goto RETRY; */ __STDIO_STREAM_SET_ERROR(stream); rv = 0; } #ifdef __UCLIBC_MJN3_ONLY__ #warning TODO: Make custom stream read return check optional. #endif #ifdef __UCLIBC_HAS_GLIBC_CUSTOM_STREAMS__ } else { assert(rv <= bufsize); if (rv > bufsize) { /* Read more than bufsize! */ abort(); } #endif } } return rv; }