/* $OpenBSD: iobuf.c,v 1.8 2015/12/05 21:27:42 mmcc Exp $ */ /* * Copyright (c) 2012 Eric Faurot <eric@openbsd.org> * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include <sys/types.h> #include <sys/socket.h> #include <sys/uio.h> #include <errno.h> #include <limits.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #ifdef IO_SSL #include <openssl/err.h> #include <openssl/ssl.h> #endif #include "iobuf.h" #define IOBUF_MAX 65536 #define IOBUFQ_MIN 4096 struct ioqbuf *ioqbuf_alloc(struct iobuf *, size_t); void iobuf_drain(struct iobuf *, size_t); int iobuf_init(struct iobuf *io, size_t size, size_t max) { memset(io, 0, sizeof *io); if (max == 0) max = IOBUF_MAX; if (size == 0) size = max; if (size > max) return (-1); if ((io->buf = malloc(size)) == NULL) return (-1); io->size = size; io->max = max; return (0); } void iobuf_clear(struct iobuf *io) { struct ioqbuf *q; free(io->buf); while ((q = io->outq)) { io->outq = q->next; free(q); } memset(io, 0, sizeof (*io)); } void iobuf_drain(struct iobuf *io, size_t n) { struct ioqbuf *q; size_t left = n; while ((q = io->outq) && left) { if ((q->wpos - q->rpos) > left) { q->rpos += left; left = 0; } else { left -= q->wpos - q->rpos; io->outq = q->next; free(q); } } io->queued -= (n - left); if (io->outq == NULL) io->outqlast = NULL; } int iobuf_extend(struct iobuf *io, size_t n) { char *t; if (n > io->max) return (-1); if (io->max - io->size < n) return (-1); t = realloc(io->buf, io->size + n); if (t == NULL) return (-1); io->size += n; io->buf = t; return (0); } size_t iobuf_left(struct iobuf *io) { return io->size - io->wpos; } size_t iobuf_space(struct iobuf *io) { return io->size - (io->wpos - io->rpos); } size_t iobuf_len(struct iobuf *io) { return io->wpos - io->rpos; } char * iobuf_data(struct iobuf *io) { return io->buf + io->rpos; } void iobuf_drop(struct iobuf *io, size_t n) { if (n >= iobuf_len(io)) { io->rpos = io->wpos = 0; return; } io->rpos += n; } char * iobuf_getline(struct iobuf *iobuf, size_t *rlen) { char *buf; size_t len, i; buf = iobuf_data(iobuf); len = iobuf_len(iobuf); for (i = 0; i + 1 <= len; i++) if (buf[i] == '\n') { /* Note: the returned address points into the iobuf * buffer. We NUL-end it for convenience, and discard * the data from the iobuf, so that the caller doesn't * have to do it. The data remains "valid" as long * as the iobuf does not overwrite it, that is until * the next call to iobuf_normalize() or iobuf_extend(). */ iobuf_drop(iobuf, i + 1); len = (i && buf[i - 1] == '\r') ? i - 1 : i; buf[len] = '\0'; if (rlen) *rlen = len; return (buf); } return (NULL); } void iobuf_normalize(struct iobuf *io) { if (io->rpos == 0) return; if (io->rpos == io->wpos) { io->rpos = io->wpos = 0; return; } memmove(io->buf, io->buf + io->rpos, io->wpos - io->rpos); io->wpos -= io->rpos; io->rpos = 0; } ssize_t iobuf_read(struct iobuf *io, int fd) { ssize_t n; n = read(fd, io->buf + io->wpos, iobuf_left(io)); if (n == -1) { /* XXX is this really what we want? */ if (errno == EAGAIN || errno == EINTR) return (IOBUF_WANT_READ); return (IOBUF_ERROR); } if (n == 0) return (IOBUF_CLOSED); io->wpos += n; return (n); } struct ioqbuf * ioqbuf_alloc(struct iobuf *io, size_t len) { struct ioqbuf *q; if (len < IOBUFQ_MIN) len = IOBUFQ_MIN; if ((q = malloc(sizeof(*q) + len)) == NULL) return (NULL); q->rpos = 0; q->wpos = 0; q->size = len; q->next = NULL; q->buf = (char *)(q) + sizeof(*q); if (io->outqlast == NULL) io->outq = q; else io->outqlast->next = q; io->outqlast = q; return (q); } size_t iobuf_queued(struct iobuf *io) { return io->queued; } void * iobuf_reserve(struct iobuf *io, size_t len) { struct ioqbuf *q; void *r; if (len == 0) return (NULL); if (((q = io->outqlast) == NULL) || q->size - q->wpos <= len) { if ((q = ioqbuf_alloc(io, len)) == NULL) return (NULL); } r = q->buf + q->wpos; q->wpos += len; io->queued += len; return (r); } int iobuf_queue(struct iobuf *io, const void *data, size_t len) { void *buf; if (len == 0) return (0); if ((buf = iobuf_reserve(io, len)) == NULL) return (-1); memmove(buf, data, len); return (len); } int iobuf_queuev(struct iobuf *io, const struct iovec *iov, int iovcnt) { int i; size_t len = 0; char *buf; for (i = 0; i < iovcnt; i++) len += iov[i].iov_len; if ((buf = iobuf_reserve(io, len)) == NULL) return (-1); for (i = 0; i < iovcnt; i++) { if (iov[i].iov_len == 0) continue; memmove(buf, iov[i].iov_base, iov[i].iov_len); buf += iov[i].iov_len; } return (0); } int iobuf_fqueue(struct iobuf *io, const char *fmt, ...) { va_list ap; int len; va_start(ap, fmt); len = iobuf_vfqueue(io, fmt, ap); va_end(ap); return (len); } int iobuf_vfqueue(struct iobuf *io, const char *fmt, va_list ap) { char *buf; int len; len = vasprintf(&buf, fmt, ap); if (len == -1) return (-1); len = iobuf_queue(io, buf, len); free(buf); return (len); } ssize_t iobuf_write(struct iobuf *io, int fd) { struct iovec iov[IOV_MAX]; struct ioqbuf *q; int i; ssize_t n; i = 0; for (q = io->outq; q ; q = q->next) { if (i >= IOV_MAX) break; iov[i].iov_base = q->buf + q->rpos; iov[i].iov_len = q->wpos - q->rpos; i++; } n = writev(fd, iov, i); if (n == -1) { if (errno == EAGAIN || errno == EINTR) return (IOBUF_WANT_WRITE); if (errno == EPIPE) return (IOBUF_CLOSED); return (IOBUF_ERROR); } iobuf_drain(io, n); return (n); } int iobuf_flush(struct iobuf *io, int fd) { ssize_t s; while (io->queued) if ((s = iobuf_write(io, fd)) < 0) return (s); return (0); } #ifdef IO_SSL int iobuf_flush_ssl(struct iobuf *io, void *ssl) { ssize_t s; while (io->queued) if ((s = iobuf_write_ssl(io, ssl)) < 0) return (s); return (0); } ssize_t iobuf_write_ssl(struct iobuf *io, void *ssl) { struct ioqbuf *q; int r; ssize_t n; q = io->outq; n = SSL_write(ssl, q->buf + q->rpos, q->wpos - q->rpos); if (n <= 0) { switch ((r = SSL_get_error(ssl, n))) { case SSL_ERROR_WANT_READ: return (IOBUF_WANT_READ); case SSL_ERROR_WANT_WRITE: return (IOBUF_WANT_WRITE); case SSL_ERROR_ZERO_RETURN: /* connection closed */ return (IOBUF_CLOSED); case SSL_ERROR_SYSCALL: if (ERR_peek_last_error()) return (IOBUF_SSLERROR); if (r == 0) errno = EPIPE; return (IOBUF_ERROR); default: return (IOBUF_SSLERROR); } } iobuf_drain(io, n); return (n); } ssize_t iobuf_read_ssl(struct iobuf *io, void *ssl) { ssize_t n; int r; n = SSL_read(ssl, io->buf + io->wpos, iobuf_left(io)); if (n < 0) { switch ((r = SSL_get_error(ssl, n))) { case SSL_ERROR_WANT_READ: return (IOBUF_WANT_READ); case SSL_ERROR_WANT_WRITE: return (IOBUF_WANT_WRITE); case SSL_ERROR_SYSCALL: if (ERR_peek_last_error()) return (IOBUF_SSLERROR); if (r == 0) errno = EPIPE; return (IOBUF_ERROR); default: return (IOBUF_SSLERROR); } } else if (n == 0) return (IOBUF_CLOSED); io->wpos += n; return (n); } #endif /* IO_SSL */