diff options
Diffstat (limited to 'contrib/pf/libevent/buffer.c')
-rw-r--r-- | contrib/pf/libevent/buffer.c | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/contrib/pf/libevent/buffer.c b/contrib/pf/libevent/buffer.c new file mode 100644 index 0000000..77efd0c --- /dev/null +++ b/contrib/pf/libevent/buffer.c @@ -0,0 +1,456 @@ +/* + * Copyright (c) 2002, 2003 Niels Provos <provos@citi.umich.edu> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#ifdef HAVE_VASPRINTF +/* If we have vasprintf, we need to define this before we include stdio.h. */ +#define _GNU_SOURCE +#endif + +#include <sys/types.h> + +#ifdef HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +#ifdef HAVE_SYS_IOCTL_H +#include <sys/ioctl.h> +#endif + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#ifdef HAVE_STDARG_H +#include <stdarg.h> +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif + +#include "event.h" + +struct evbuffer * +evbuffer_new(void) +{ + struct evbuffer *buffer; + + buffer = calloc(1, sizeof(struct evbuffer)); + + return (buffer); +} + +void +evbuffer_free(struct evbuffer *buffer) +{ + if (buffer->orig_buffer != NULL) + free(buffer->orig_buffer); + free(buffer); +} + +/* + * This is a destructive add. The data from one buffer moves into + * the other buffer. + */ + +#define SWAP(x,y) do { \ + (x)->buffer = (y)->buffer; \ + (x)->orig_buffer = (y)->orig_buffer; \ + (x)->misalign = (y)->misalign; \ + (x)->totallen = (y)->totallen; \ + (x)->off = (y)->off; \ +} while (0) + +int +evbuffer_add_buffer(struct evbuffer *outbuf, struct evbuffer *inbuf) +{ + int res; + + /* Short cut for better performance */ + if (outbuf->off == 0) { + struct evbuffer tmp; + size_t oldoff = inbuf->off; + + /* Swap them directly */ + SWAP(&tmp, outbuf); + SWAP(outbuf, inbuf); + SWAP(inbuf, &tmp); + + /* + * Optimization comes with a price; we need to notify the + * buffer if necessary of the changes. oldoff is the amount + * of data that we tranfered from inbuf to outbuf + */ + if (inbuf->off != oldoff && inbuf->cb != NULL) + (*inbuf->cb)(inbuf, oldoff, inbuf->off, inbuf->cbarg); + if (oldoff && outbuf->cb != NULL) + (*outbuf->cb)(outbuf, 0, oldoff, outbuf->cbarg); + + return (0); + } + + res = evbuffer_add(outbuf, inbuf->buffer, inbuf->off); + if (res == 0) { + /* We drain the input buffer on success */ + evbuffer_drain(inbuf, inbuf->off); + } + + return (res); +} + +int +evbuffer_add_vprintf(struct evbuffer *buf, const char *fmt, va_list ap) +{ + char *buffer; + size_t space; + size_t oldoff = buf->off; + int sz; + va_list aq; + + for (;;) { + buffer = (char *)buf->buffer + buf->off; + space = buf->totallen - buf->misalign - buf->off; + +#ifndef va_copy +#define va_copy(dst, src) memcpy(&(dst), &(src), sizeof(va_list)) +#endif + va_copy(aq, ap); + +#ifdef WIN32 + sz = vsnprintf(buffer, space - 1, fmt, aq); + buffer[space - 1] = '\0'; +#else + sz = vsnprintf(buffer, space, fmt, aq); +#endif + + va_end(aq); + + if (sz == -1) + return (-1); + if (sz < space) { + buf->off += sz; + if (buf->cb != NULL) + (*buf->cb)(buf, oldoff, buf->off, buf->cbarg); + return (sz); + } + if (evbuffer_expand(buf, sz + 1) == -1) + return (-1); + + } + /* NOTREACHED */ +} + +int +evbuffer_add_printf(struct evbuffer *buf, const char *fmt, ...) +{ + int res = -1; + va_list ap; + + va_start(ap, fmt); + res = evbuffer_add_vprintf(buf, fmt, ap); + va_end(ap); + + return (res); +} + +/* Reads data from an event buffer and drains the bytes read */ + +int +evbuffer_remove(struct evbuffer *buf, void *data, size_t datlen) +{ + size_t nread = datlen; + if (nread >= buf->off) + nread = buf->off; + + memcpy(data, buf->buffer, nread); + evbuffer_drain(buf, nread); + + return (nread); +} + +/* + * Reads a line terminated by either '\r\n', '\n\r' or '\r' or '\n'. + * The returned buffer needs to be freed by the called. + */ + +char * +evbuffer_readline(struct evbuffer *buffer) +{ + u_char *data = EVBUFFER_DATA(buffer); + size_t len = EVBUFFER_LENGTH(buffer); + char *line; + unsigned int i; + + for (i = 0; i < len; i++) { + if (data[i] == '\r' || data[i] == '\n') + break; + } + + if (i == len) + return (NULL); + + if ((line = malloc(i + 1)) == NULL) { + fprintf(stderr, "%s: out of memory\n", __func__); + evbuffer_drain(buffer, i); + return (NULL); + } + + memcpy(line, data, i); + line[i] = '\0'; + + /* + * Some protocols terminate a line with '\r\n', so check for + * that, too. + */ + if ( i < len - 1 ) { + char fch = data[i], sch = data[i+1]; + + /* Drain one more character if needed */ + if ( (sch == '\r' || sch == '\n') && sch != fch ) + i += 1; + } + + evbuffer_drain(buffer, i + 1); + + return (line); +} + +/* Adds data to an event buffer */ + +static inline void +evbuffer_align(struct evbuffer *buf) +{ + memmove(buf->orig_buffer, buf->buffer, buf->off); + buf->buffer = buf->orig_buffer; + buf->misalign = 0; +} + +/* Expands the available space in the event buffer to at least datlen */ + +int +evbuffer_expand(struct evbuffer *buf, size_t datlen) +{ + size_t need = buf->misalign + buf->off + datlen; + + /* If we can fit all the data, then we don't have to do anything */ + if (buf->totallen >= need) + return (0); + + /* + * If the misalignment fulfills our data needs, we just force an + * alignment to happen. Afterwards, we have enough space. + */ + if (buf->misalign >= datlen) { + evbuffer_align(buf); + } else { + void *newbuf; + size_t length = buf->totallen; + + if (length < 256) + length = 256; + while (length < need) + length <<= 1; + + if (buf->orig_buffer != buf->buffer) + evbuffer_align(buf); + if ((newbuf = realloc(buf->buffer, length)) == NULL) + return (-1); + + buf->orig_buffer = buf->buffer = newbuf; + buf->totallen = length; + } + + return (0); +} + +int +evbuffer_add(struct evbuffer *buf, const void *data, size_t datlen) +{ + size_t need = buf->misalign + buf->off + datlen; + size_t oldoff = buf->off; + + if (buf->totallen < need) { + if (evbuffer_expand(buf, datlen) == -1) + return (-1); + } + + memcpy(buf->buffer + buf->off, data, datlen); + buf->off += datlen; + + if (datlen && buf->cb != NULL) + (*buf->cb)(buf, oldoff, buf->off, buf->cbarg); + + return (0); +} + +void +evbuffer_drain(struct evbuffer *buf, size_t len) +{ + size_t oldoff = buf->off; + + if (len >= buf->off) { + buf->off = 0; + buf->buffer = buf->orig_buffer; + buf->misalign = 0; + goto done; + } + + buf->buffer += len; + buf->misalign += len; + + buf->off -= len; + + done: + /* Tell someone about changes in this buffer */ + if (buf->off != oldoff && buf->cb != NULL) + (*buf->cb)(buf, oldoff, buf->off, buf->cbarg); + +} + +/* + * Reads data from a file descriptor into a buffer. + */ + +#define EVBUFFER_MAX_READ 4096 + +int +evbuffer_read(struct evbuffer *buf, int fd, int howmuch) +{ + u_char *p; + size_t oldoff = buf->off; + int n = EVBUFFER_MAX_READ; +#ifdef WIN32 + DWORD dwBytesRead; +#endif + +#ifdef FIONREAD + if (ioctl(fd, FIONREAD, &n) == -1 || n == 0) { + n = EVBUFFER_MAX_READ; + } else if (n > EVBUFFER_MAX_READ && n > howmuch) { + /* + * It's possible that a lot of data is available for + * reading. We do not want to exhaust resources + * before the reader has a chance to do something + * about it. If the reader does not tell us how much + * data we should read, we artifically limit it. + */ + if (n > buf->totallen << 2) + n = buf->totallen << 2; + if (n < EVBUFFER_MAX_READ) + n = EVBUFFER_MAX_READ; + } +#endif + if (howmuch < 0 || howmuch > n) + howmuch = n; + + /* If we don't have FIONREAD, we might waste some space here */ + if (evbuffer_expand(buf, howmuch) == -1) + return (-1); + + /* We can append new data at this point */ + p = buf->buffer + buf->off; + +#ifndef WIN32 + n = read(fd, p, howmuch); + if (n == -1) + return (-1); + if (n == 0) + return (0); +#else + n = ReadFile((HANDLE)fd, p, howmuch, &dwBytesRead, NULL); + if (n == 0) + return (-1); + if (dwBytesRead == 0) + return (0); + n = dwBytesRead; +#endif + + buf->off += n; + + /* Tell someone about changes in this buffer */ + if (buf->off != oldoff && buf->cb != NULL) + (*buf->cb)(buf, oldoff, buf->off, buf->cbarg); + + return (n); +} + +int +evbuffer_write(struct evbuffer *buffer, int fd) +{ + int n; +#ifdef WIN32 + DWORD dwBytesWritten; +#endif + +#ifndef WIN32 + n = write(fd, buffer->buffer, buffer->off); + if (n == -1) + return (-1); + if (n == 0) + return (0); +#else + n = WriteFile((HANDLE)fd, buffer->buffer, buffer->off, &dwBytesWritten, NULL); + if (n == 0) + return (-1); + if (dwBytesWritten == 0) + return (0); + n = dwBytesWritten; +#endif + evbuffer_drain(buffer, n); + + return (n); +} + +u_char * +evbuffer_find(struct evbuffer *buffer, const u_char *what, size_t len) +{ + size_t remain = buffer->off; + u_char *search = buffer->buffer; + u_char *p; + + while ((p = memchr(search, *what, remain)) != NULL) { + remain = buffer->off - (size_t)(search - buffer->buffer); + if (remain < len) + break; + if (memcmp(p, what, len) == 0) + return (p); + search = p + 1; + } + + return (NULL); +} + +void evbuffer_setcb(struct evbuffer *buffer, + void (*cb)(struct evbuffer *, size_t, size_t, void *), + void *cbarg) +{ + buffer->cb = cb; + buffer->cbarg = cbarg; +} |