lighttpd 1.4.x https://www.lighttpd.net/
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#include "first.h"
/**
* the network chunk-API
*
*
*/
#include "chunk.h"
#include "fdevent.h"
#include "log.h"
#include <sys/types.h>
#include <sys/stat.h>
#include "sys-mmap.h"
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
/* default 1MB, upper limit 128MB */
#define DEFAULT_TEMPFILE_SIZE (1 * 1024 * 1024)
#define MAX_TEMPFILE_SIZE (128 * 1024 * 1024)
static size_t chunk_buf_sz = 8192;
static chunk *chunks, *chunks_oversized;
static chunk *chunk_buffers;
static const array *chunkqueue_default_tempdirs = NULL;
static off_t chunkqueue_default_tempfile_size = DEFAULT_TEMPFILE_SIZE;
void chunkqueue_set_chunk_size (size_t sz)
{
chunk_buf_sz = sz > 0 ? ((sz + 1023) & ~1023uL) : 8192;
}
void chunkqueue_set_tempdirs_default_reset (void)
{
chunkqueue_default_tempdirs = NULL;
chunkqueue_default_tempfile_size = DEFAULT_TEMPFILE_SIZE;
}
/* chunk buffer (c->mem) is never NULL; specialize routines from buffer.h */
__attribute_pure__
static inline size_t chunk_buffer_string_length(const buffer *b) {
return 0 != b->used ? b->used - 1 : 0;
}
__attribute_pure__
static inline int chunk_buffer_string_is_empty(const buffer *b) {
return b->used < 2;
}
__attribute_pure__
static inline size_t chunk_buffer_string_space(const buffer *b) {
return b->size ? b->size - (b->used | (0 == b->used)) : 0;
}
chunkqueue *chunkqueue_init(chunkqueue *cq) {
/* (if caller passes non-NULL cq, it must be 0-init) */
if (NULL == cq) {
cq = calloc(1, sizeof(*cq));
force_assert(NULL != cq);
}
cq->first = NULL;
cq->last = NULL;
cq->tempdirs = chunkqueue_default_tempdirs;
cq->upload_temp_file_size = chunkqueue_default_tempfile_size;
return cq;
}
__attribute_returns_nonnull__
static chunk *chunk_init(size_t sz) {
chunk *c;
c = calloc(1, sizeof(*c));
force_assert(NULL != c);
c->type = MEM_CHUNK;
c->mem = buffer_init();
c->file.start = c->file.length = c->file.mmap.offset = 0;
c->file.fd = -1;
c->file.mmap.start = MAP_FAILED;
c->file.mmap.length = 0;
c->file.is_temp = 0;
c->offset = 0;
c->next = NULL;
buffer_string_prepare_copy(c->mem, sz-1);
return c;
}
static void chunk_reset_file_chunk(chunk *c) {
if (c->file.is_temp && !chunk_buffer_string_is_empty(c->mem)) {
unlink(c->mem->ptr);
}
if (c->file.fd != -1) {
close(c->file.fd);
c->file.fd = -1;
}
if (MAP_FAILED != c->file.mmap.start) {
munmap(c->file.mmap.start, c->file.mmap.length);
c->file.mmap.start = MAP_FAILED;
}
c->file.start = c->file.length = c->file.mmap.offset = 0;
c->file.mmap.length = 0;
c->file.is_temp = 0;
c->type = MEM_CHUNK;
}
static void chunk_reset(chunk *c) {
if (c->type == FILE_CHUNK) chunk_reset_file_chunk(c);
buffer_clear(c->mem);
c->offset = 0;
}
static void chunk_free(chunk *c) {
if (c->type == FILE_CHUNK) chunk_reset_file_chunk(c);
buffer_free(c->mem);
free(c);
}
buffer * chunk_buffer_acquire(void) {
chunk *c;
buffer *b;
if (chunks) {
c = chunks;
chunks = c->next;
}
else {
c = chunk_init(chunk_buf_sz);
}
c->next = chunk_buffers;
chunk_buffers = c;
b = c->mem;
c->mem = NULL;
return b;
}
void chunk_buffer_release(buffer *b) {
if (NULL == b) return;
if (b->size >= chunk_buf_sz && chunk_buffers) {
chunk *c = chunk_buffers;
chunk_buffers = c->next;
c->mem = b;
c->next = chunks;
chunks = c;
buffer_clear(b);
}
else {
buffer_free(b);
}
}
__attribute_returns_nonnull__
static chunk * chunk_acquire(size_t sz) {
if (sz <= chunk_buf_sz) {
if (chunks) {
chunk *c = chunks;
chunks = c->next;
return c;
}
sz = chunk_buf_sz;
}
else {
sz = (sz + 8191) & ~8191uL;
/* future: might have buckets of certain sizes, up to socket buf sizes*/
if (chunks_oversized && chunks_oversized->mem->size >= sz) {
chunk *c = chunks_oversized;
chunks_oversized = c->next;
return c;
}
}
return chunk_init(sz);
}
static void chunk_release(chunk *c) {
const size_t sz = c->mem->size;
if (sz == chunk_buf_sz) {
chunk_reset(c);
c->next = chunks;
chunks = c;
}
else if (sz > chunk_buf_sz) {
chunk_reset(c);
chunk **co = &chunks_oversized;
while (*co && sz < (*co)->mem->size) co = &(*co)->next;
c->next = *co;
*co = c;
}
else {
chunk_free(c);
}
}
void chunkqueue_chunk_pool_clear(void)
{
for (chunk *next, *c = chunks; c; c = next) {
next = c->next;
chunk_free(c);
}
chunks = NULL;
for (chunk *next, *c = chunks_oversized; c; c = next) {
next = c->next;
chunk_free(c);
}
chunks_oversized = NULL;
}
void chunkqueue_chunk_pool_free(void)
{
chunkqueue_chunk_pool_clear();
for (chunk *next, *c = chunk_buffers; c; c = next) {
next = c->next;
c->mem = buffer_init(); /*(chunk_reset() expects c->mem != NULL)*/
chunk_free(c);
}
chunk_buffers = NULL;
}
__attribute_pure__
static off_t chunk_remaining_length(const chunk *c) {
/* MEM_CHUNK or FILE_CHUNK */
return (c->type == MEM_CHUNK
? (off_t)chunk_buffer_string_length(c->mem)
: c->file.length)
- c->offset;
}
static void chunkqueue_release_chunks(chunkqueue *cq) {
cq->last = NULL;
for (chunk *c; (c = cq->first); ) {
cq->first = c->next;
chunk_release(c);
}
}
void chunkqueue_free(chunkqueue *cq) {
if (NULL == cq) return;
chunkqueue_release_chunks(cq);
free(cq);
}
static void chunkqueue_prepend_chunk(chunkqueue * const restrict cq, chunk * const restrict c) {
if (NULL == (c->next = cq->first)) cq->last = c;
cq->first = c;
}
static void chunkqueue_append_chunk(chunkqueue * const restrict cq, chunk * const restrict c) {
c->next = NULL;
*(cq->last ? &cq->last->next : &cq->first) = c;
cq->last = c;
}
__attribute_returns_nonnull__
static chunk * chunkqueue_prepend_mem_chunk(chunkqueue *cq, size_t sz) {
chunk *c = chunk_acquire(sz);
chunkqueue_prepend_chunk(cq, c);
return c;
}
__attribute_returns_nonnull__
static chunk * chunkqueue_append_mem_chunk(chunkqueue *cq, size_t sz) {
chunk *c = chunk_acquire(sz);
chunkqueue_append_chunk(cq, c);
return c;
}
__attribute_returns_nonnull__
static chunk * chunkqueue_append_file_chunk(chunkqueue * const restrict cq, const buffer * const restrict fn, off_t offset, off_t len) {
chunk *c = chunk_acquire(buffer_string_length(fn)+1);
chunkqueue_append_chunk(cq, c);
c->type = FILE_CHUNK;
c->file.start = offset;
c->file.length = len;
cq->bytes_in += len;
buffer_copy_buffer(c->mem, fn);
return c;
}
void chunkqueue_reset(chunkqueue *cq) {
chunkqueue_release_chunks(cq);
cq->bytes_in = 0;
cq->bytes_out = 0;
cq->tempdir_idx = 0;
}
void chunkqueue_append_file_fd(chunkqueue * const restrict cq, const buffer * const restrict fn, int fd, off_t offset, off_t len) {
if (len > 0) {
(chunkqueue_append_file_chunk(cq, fn, offset, len))->file.fd = fd;
}
else {
close(fd);
}
}
void chunkqueue_append_file(chunkqueue * const restrict cq, const buffer * const restrict fn, off_t offset, off_t len) {
if (len > 0) {
chunkqueue_append_file_chunk(cq, fn, offset, len);
}
}
static int chunkqueue_append_mem_extend_chunk(chunkqueue * const restrict cq, const char * const restrict mem, size_t len) {
chunk *c = cq->last;
if (0 == len) return 1;
if (c != NULL && c->type == MEM_CHUNK
&& chunk_buffer_string_space(c->mem) >= len) {
buffer_append_string_len(c->mem, mem, len);
cq->bytes_in += len;
return 1;
}
return 0;
}
void chunkqueue_append_buffer(chunkqueue * const restrict cq, buffer * const restrict mem) {
chunk *c;
size_t len = buffer_string_length(mem);
if (len < 256 && chunkqueue_append_mem_extend_chunk(cq, mem->ptr, len)) return;
c = chunkqueue_append_mem_chunk(cq, chunk_buf_sz);
cq->bytes_in += len;
buffer_move(c->mem, mem);
}
void chunkqueue_append_mem(chunkqueue * const restrict cq, const char * const restrict mem, size_t len) {
chunk *c;
if (len < chunk_buf_sz && chunkqueue_append_mem_extend_chunk(cq, mem, len))
return;
c = chunkqueue_append_mem_chunk(cq, len+1);
cq->bytes_in += len;
buffer_copy_string_len(c->mem, mem, len);
}
void chunkqueue_append_mem_min(chunkqueue * const restrict cq, const char * const restrict mem, size_t len) {
chunk *c;
if (len < chunk_buf_sz && chunkqueue_append_mem_extend_chunk(cq, mem, len))
return;
c = chunk_init(len+1);
chunkqueue_append_chunk(cq, c);
cq->bytes_in += len;
buffer_copy_string_len(c->mem, mem, len);
}
void chunkqueue_append_chunkqueue(chunkqueue * const restrict cq, chunkqueue * const restrict src) {
if (src == NULL || NULL == src->first) return;
if (NULL == cq->first) {
cq->first = src->first;
} else {
cq->last->next = src->first;
}
cq->last = src->last;
cq->bytes_in += chunkqueue_length(src);
src->first = NULL;
src->last = NULL;
src->bytes_out = src->bytes_in;
}
buffer * chunkqueue_prepend_buffer_open_sz(chunkqueue *cq, size_t sz) {
chunk * const c = chunkqueue_prepend_mem_chunk(cq, sz);
return c->mem;
}
buffer * chunkqueue_prepend_buffer_open(chunkqueue *cq) {
return chunkqueue_prepend_buffer_open_sz(cq, chunk_buf_sz);
}
void chunkqueue_prepend_buffer_commit(chunkqueue *cq) {
cq->bytes_in += chunk_buffer_string_length(cq->first->mem);
}
buffer * chunkqueue_append_buffer_open_sz(chunkqueue *cq, size_t sz) {
chunk * const c = chunkqueue_append_mem_chunk(cq, sz);
return c->mem;
}
buffer * chunkqueue_append_buffer_open(chunkqueue *cq) {
return chunkqueue_append_buffer_open_sz(cq, chunk_buf_sz);
}
void chunkqueue_append_buffer_commit(chunkqueue *cq) {
cq->bytes_in += chunk_buffer_string_length(cq->last->mem);
}
static void chunkqueue_remove_empty_chunks(chunkqueue *cq);
char * chunkqueue_get_memory(chunkqueue * const restrict cq, size_t * const restrict len) {
size_t sz = *len ? *len : (chunk_buf_sz >> 1);
buffer *b;
chunk *c = cq->last;
if (NULL != c && MEM_CHUNK == c->type) {
/* return pointer into existing buffer if large enough */
size_t avail = chunk_buffer_string_space(c->mem);
if (avail >= sz) {
*len = avail;
b = c->mem;
return b->ptr + chunk_buffer_string_length(b);
}
}
/* allocate new chunk */
b = chunkqueue_append_buffer_open_sz(cq, sz);
*len = chunk_buffer_string_space(b);
return b->ptr;
}
void chunkqueue_use_memory(chunkqueue * const restrict cq, chunk *ckpt, size_t len) {
buffer *b = cq->last->mem;
if (len > 0) {
buffer_commit(b, len);
cq->bytes_in += len;
if (cq->last == ckpt || NULL == ckpt || MEM_CHUNK != ckpt->type
|| len > chunk_buffer_string_space(ckpt->mem)) return;
buffer_append_string_buffer(ckpt->mem, b);
}
else if (!chunk_buffer_string_is_empty(b)) { /*(cq->last == ckpt)*/
return; /* last chunk is not empty */
}
/* remove empty last chunk */
chunk_release(cq->last);
cq->last = ckpt;
*(ckpt ? &ckpt->next : &cq->first) = NULL;
}
void chunkqueue_update_file(chunkqueue * const restrict cq, chunk *c, off_t len) {
/*assert(c->type == FILE_CHUNK);*/
c->file.length += len;
cq->bytes_in += len;
}
void chunkqueue_set_tempdirs_default (const array *tempdirs, off_t upload_temp_file_size) {
chunkqueue_default_tempdirs = tempdirs;
chunkqueue_default_tempfile_size
= (0 == upload_temp_file_size) ? DEFAULT_TEMPFILE_SIZE
: (upload_temp_file_size > MAX_TEMPFILE_SIZE) ? MAX_TEMPFILE_SIZE
: upload_temp_file_size;
}
void chunkqueue_set_tempdirs(chunkqueue * const restrict cq, const array * const restrict tempdirs, off_t upload_temp_file_size) {
force_assert(NULL != cq);
cq->tempdirs = tempdirs;
cq->upload_temp_file_size
= (0 == upload_temp_file_size) ? DEFAULT_TEMPFILE_SIZE
: (upload_temp_file_size > MAX_TEMPFILE_SIZE) ? MAX_TEMPFILE_SIZE
: upload_temp_file_size;
cq->tempdir_idx = 0;
}
void chunkqueue_steal(chunkqueue * const restrict dest, chunkqueue * const restrict src, off_t len) {
while (len > 0) {
chunk *c = src->first;
off_t clen = 0, use;
if (NULL == c) break;
clen = chunk_remaining_length(c);
if (0 == clen) {
/* drop empty chunk */
src->first = c->next;
if (c == src->last) src->last = NULL;
chunk_release(c);
continue;
}
use = len >= clen ? clen : len;
len -= use;
if (use == clen) {
/* move complete chunk */
src->first = c->next;
if (c == src->last) src->last = NULL;
chunkqueue_append_chunk(dest, c);
dest->bytes_in += use;
} else {
/* partial chunk with length "use" */
switch (c->type) {
case MEM_CHUNK:
chunkqueue_append_mem(dest, c->mem->ptr + c->offset, use);
break;
case FILE_CHUNK:
/* tempfile flag is in "last" chunk after the split */
chunkqueue_append_file(dest, c->mem, c->file.start + c->offset, use);
break;
}
c->offset += use;
force_assert(0 == len);
}
src->bytes_out += use;
}
}
static chunk *chunkqueue_get_append_tempfile(chunkqueue * const restrict cq, log_error_st * const restrict errh) {
chunk *c;
buffer *template = buffer_init_string("/var/tmp/lighttpd-upload-XXXXXX");
int fd = -1;
if (cq->tempdirs && cq->tempdirs->used) {
/* we have several tempdirs, only if all of them fail we jump out */
for (errno = EIO; cq->tempdir_idx < cq->tempdirs->used; ++cq->tempdir_idx) {
data_string *ds = (data_string *)cq->tempdirs->data[cq->tempdir_idx];
buffer_copy_buffer(template, &ds->value);
buffer_append_path_len(template, CONST_STR_LEN("lighttpd-upload-XXXXXX"));
if (-1 != (fd = fdevent_mkstemp_append(template->ptr))) break;
}
} else {
fd = fdevent_mkstemp_append(template->ptr);
}
if (fd < 0) {
/* (report only the last error to mkstemp()
* if multiple temp dirs attempted) */
log_perror(errh, __FILE__, __LINE__,
"opening temp-file failed: %s", template->ptr);
buffer_free(template);
return NULL;
}
c = chunkqueue_append_file_chunk(cq, template, 0, 0);
c->file.fd = fd;
c->file.is_temp = 1;
buffer_free(template);
return c;
}
int chunkqueue_append_mem_to_tempfile(chunkqueue * const restrict dest, const char * restrict mem, size_t len, log_error_st * const restrict errh) {
chunk *dst_c;
ssize_t written;
do {
/*
* if the last chunk is
* - smaller than dest->upload_temp_file_size
* - not read yet (offset == 0)
* -> append to it (so it might actually become larger than dest->upload_temp_file_size)
* otherwise
* -> create a new chunk
*
* */
dst_c = dest->last;
if (NULL != dst_c
&& FILE_CHUNK == dst_c->type
&& dst_c->file.is_temp
&& dst_c->file.fd >= 0
&& 0 == dst_c->offset) {
/* ok, take the last chunk for our job */
if (dst_c->file.length >= (off_t)dest->upload_temp_file_size) {
/* the chunk is too large now, close it */
int rc = close(dst_c->file.fd);
dst_c->file.fd = -1;
if (0 != rc) {
log_perror(errh, __FILE__, __LINE__,
"close() temp-file %s failed", dst_c->mem->ptr);
return -1;
}
dst_c = NULL;
}
} else {
dst_c = NULL;
}
if (NULL == dst_c && NULL == (dst_c = chunkqueue_get_append_tempfile(dest, errh))) {
return -1;
}
#ifdef __COVERITY__
if (dst_c->file.fd < 0) return -1;
#endif
/* (dst_c->file.fd >= 0) */
/* coverity[negative_returns : FALSE] */
written = write(dst_c->file.fd, mem, len);
if ((size_t) written == len) {
dst_c->file.length += len;
dest->bytes_in += len;
return 0;
} else if (written >= 0) {
/*(assume EINTR if partial write and retry write();
* retry write() might fail with ENOSPC if no more space on volume)*/
dest->bytes_in += written;
mem += written;
len -= (size_t)written;
dst_c->file.length += (size_t)written;
/* continue; retry */
} else if (errno == EINTR) {
/* continue; retry */
} else {
int retry = (errno == ENOSPC && dest->tempdirs && ++dest->tempdir_idx < dest->tempdirs->used);
if (!retry) {
log_perror(errh, __FILE__, __LINE__,
"write() temp-file %s failed", dst_c->mem->ptr);
}
if (0 == chunk_remaining_length(dst_c)) {
/*(remove empty chunk and unlink tempfile)*/
chunkqueue_remove_empty_chunks(dest);
} else {/*(close tempfile; avoid later attempts to append)*/
int rc = close(dst_c->file.fd);
dst_c->file.fd = -1;
if (0 != rc) {
log_perror(errh, __FILE__, __LINE__,
"close() temp-file %s failed", dst_c->mem->ptr);
return -1;
}
}
if (!retry) break; /* return -1; */
/* continue; retry */
}
} while (dst_c);
return -1;
}
int chunkqueue_steal_with_tempfiles(chunkqueue * const restrict dest, chunkqueue * const restrict src, off_t len, log_error_st * const restrict errh) {
while (len > 0) {
chunk *c = src->first;
off_t clen = 0, use;
if (NULL == c) break;
clen = chunk_remaining_length(c);
if (0 == clen) {
/* drop empty chunk */
src->first = c->next;
if (c == src->last) src->last = NULL;
chunk_release(c);
continue;
}
use = (len >= clen) ? clen : len;
len -= use;
switch (c->type) {
case FILE_CHUNK:
if (use == clen) {
/* move complete chunk */
src->first = c->next;
if (c == src->last) src->last = NULL;
chunkqueue_append_chunk(dest, c);
dest->bytes_in += use;
} else {
/* partial chunk with length "use" */
/* tempfile flag is in "last" chunk after the split */
chunkqueue_append_file(dest, c->mem, c->file.start + c->offset, use);
c->offset += use;
force_assert(0 == len);
}
break;
case MEM_CHUNK:
/* store "use" bytes from memory chunk in tempfile */
if (0 != chunkqueue_append_mem_to_tempfile(dest, c->mem->ptr + c->offset, use, errh)) {
return -1;
}
if (use == clen) {
/* finished chunk */
src->first = c->next;
if (c == src->last) src->last = NULL;
chunk_release(c);
} else {
/* partial chunk */
c->offset += use;
force_assert(0 == len);
}
break;
}
src->bytes_out += use;
}
return 0;
}
void chunkqueue_mark_written(chunkqueue *cq, off_t len) {
cq->bytes_out += len;
for (chunk *c; (c = cq->first); ) {
off_t c_len = chunk_remaining_length(c);
if (len >= c_len) { /* chunk got finished */
len -= c_len;
cq->first = c->next;
chunk_release(c);
if (0 == len) break;
}
else { /* partial chunk */
c->offset += len;
return; /* chunk not finished */
}
}
if (NULL == cq->first)
cq->last = NULL;
else
chunkqueue_remove_finished_chunks(cq);
}
void chunkqueue_remove_finished_chunks(chunkqueue *cq) {
for (chunk *c; (c = cq->first) && 0 == chunk_remaining_length(c); ){
if (NULL == (cq->first = c->next)) cq->last = NULL;
chunk_release(c);
}
}
static void chunkqueue_remove_empty_chunks(chunkqueue *cq) {
chunk *c;
chunkqueue_remove_finished_chunks(cq);
for (c = cq->first; c && c->next; c = c->next) {
if (0 == chunk_remaining_length(c->next)) {
chunk *empty = c->next;
c->next = empty->next;
if (empty == cq->last) cq->last = c;
chunk_release(empty);
}
}
}
void chunkqueue_compact_mem(chunkqueue *cq, size_t clen) {
chunk *c = cq->first;
buffer *b = c->mem;
size_t len = buffer_string_length(b) - c->offset;
if (b->size > clen) {
if (0 != c->offset) {
memmove(b->ptr, b->ptr+c->offset, len);
buffer_string_set_length(b, len);
c->offset = 0;
}
}
else {
b = chunkqueue_prepend_buffer_open_sz(cq, clen + 8192);
buffer_append_string_len(b, c->mem->ptr + c->offset, len);
cq->first->next = c->next;
if (NULL == c->next) cq->last = cq->first;
chunk_release(c);
c = cq->first;
}
for (chunk *fc = c; ((clen -= len) && (c = fc->next)); ) {
len = buffer_string_length(c->mem) - c->offset;
if (len > clen) len = clen;
buffer_append_string_len(b, c->mem->ptr + c->offset, len);
fc->next = c->next;
if (NULL == c->next) cq->last = fc;
chunk_release(c);
}
/* chunkqueue_prepend_buffer_commit() is not called here;
* no data added/removed from chunkqueue; consolidated only */
}
static int chunk_open_file_chunk(chunk * const restrict c, log_error_st * const restrict errh) {
off_t offset, toSend;
struct stat st;
force_assert(NULL != c);
force_assert(FILE_CHUNK == c->type);
force_assert(c->offset >= 0 && c->offset <= c->file.length);
offset = c->file.start + c->offset;
toSend = c->file.length - c->offset;
if (-1 == c->file.fd) {
/* (permit symlinks; should already have been checked. However, TOC-TOU remains) */
if (-1 == (c->file.fd = fdevent_open_cloexec(c->mem->ptr, 1, O_RDONLY, 0))) {
log_perror(errh, __FILE__, __LINE__, "open failed: %s",c->mem->ptr);
return -1;
}
}
/*(skip file size checks if file is temp file created by lighttpd)*/
if (c->file.is_temp) return 0;
if (-1 == fstat(c->file.fd, &st)) {
log_perror(errh, __FILE__, __LINE__, "fstat failed");
return -1;
}
if (offset > st.st_size || toSend > st.st_size || offset > st.st_size - toSend) {
log_error(errh, __FILE__, __LINE__, "file shrunk: %s", c->mem->ptr);
return -1;
}
return 0;
}
int chunkqueue_open_file_chunk(chunkqueue * const restrict cq, log_error_st * const restrict errh) {
return chunk_open_file_chunk(cq->first, errh);
}
void
chunkqueue_small_resp_optim (chunkqueue * const restrict cq)
{
/*(caller must verify response is small (and non-empty) before calling)*/
/*(optimization to use fewer syscalls to send a small response by reading
* small files into memory, thereby avoiding use of sendfile() and multiple
* calls to writev() (benefit for cleartext (non-TLS) and <= HTTP/1.1))
*(If TLS, then will shortly need to be in memory for encryption anyway)*/
/*assert(cq->first);*/
chunk *c = cq->first;
chunk * const filec = c->next;
if (c->type != MEM_CHUNK || filec != cq->last || filec->type != FILE_CHUNK)
return;
const int fd = filec->file.fd;
if (fd < 0) return; /*(require that file already be open)*/
off_t offset = filec->file.start + filec->offset;
if (0 != offset && -1 == lseek(fd, offset, SEEK_SET)) return;
/* Note: there should be no size change in chunkqueue,
* so cq->bytes_in and cq->bytes_out should not be modified */
buffer *b = c->mem;
off_t len = filec->file.length - filec->offset;
if ((size_t)len > chunk_buffer_string_space(b)) {
chunk * const nc = chunk_acquire((size_t)len+1);
c->next = nc;
nc->next = filec;
b = nc->mem;
}
char * const ptr = b->ptr + chunk_buffer_string_length(b);
ssize_t rd;
offset = 0; /*(reuse offset var for offset into mem buffer)*/
do {
rd = read(fd, ptr+offset, len-offset);
} while (rd > 0 ? (offset += rd, len -= rd) : errno == EINTR);
/*(contents of chunkqueue kept valid even if error reading from file)*/
buffer_commit(b, offset);
filec->offset += offset;
chunkqueue_remove_empty_chunks(cq);
}
int
chunkqueue_peek_data (chunkqueue * const cq,
char ** const data, uint32_t * const dlen,
log_error_st * const errh)
{
char * const data_in = *data;
const uint32_t data_insz = *dlen;
*dlen = 0;
for (chunk *c = cq->first; c; ) {
uint32_t space = data_insz - *dlen;
switch (c->type) {
case MEM_CHUNK:
{
uint32_t have = buffer_string_length(c->mem) - (uint32_t)c->offset;
if (have > space)
have = space;
if (*dlen)
memcpy(data_in + *dlen, c->mem->ptr + c->offset, have);
else
*data = c->mem->ptr + c->offset; /*(reference; defer copy)*/
*dlen += have;
break;
}
case FILE_CHUNK:
if (c->file.fd >= 0 || 0 == chunk_open_file_chunk(c, errh)) {
off_t offset = c->file.start + c->offset;
off_t toSend = c->file.length - c->offset;
if (toSend > (off_t)space)
toSend = (off_t)space;
if (-1 == lseek(c->file.fd, offset, SEEK_SET)) {
log_perror(errh, __FILE__, __LINE__, "lseek");
return -1;
}
toSend = read(c->file.fd, data_in + *dlen, (size_t)toSend);
if (toSend <= 0) { /* -1 error; 0 EOF (unexpected) */
log_perror(errh, __FILE__, __LINE__, "read");
return -1;
}
*dlen += (uint32_t)toSend;
break;
}
return -1;
default:
return -1;
}
if (*dlen == data_insz)
break;
c = c->next;
if (NULL == c)
break;
if (*dlen && *data != data_in) {
memcpy(data_in, *data, *dlen);
*data = data_in;
}
}
return 0;
}
int
chunkqueue_read_data (chunkqueue * const cq,
char * const data, const uint32_t dlen,
log_error_st * const errh)
{
char *ptr = data;
uint32_t len = dlen;
if (chunkqueue_peek_data(cq, &ptr, &len, errh) < 0 || len != dlen)
return -1;
if (data != ptr) memcpy(data, ptr, len);
chunkqueue_mark_written(cq, len);
return 0;
}
buffer *
chunkqueue_read_squash (chunkqueue * const restrict cq, log_error_st * const restrict errh)
{
/* read and replace chunkqueue contents with single MEM_CHUNK.
* cq->bytes_out is not modified */
off_t cqlen = chunkqueue_length(cq);
if (cqlen >= UINT32_MAX) return NULL;
if (cq->first && NULL == cq->first->next && cq->first->type == MEM_CHUNK)
return cq->first->mem;
chunk * const c = chunk_acquire((uint32_t)cqlen+1);
char *data = c->mem->ptr;
uint32_t dlen = (uint32_t)cqlen;
int rc = chunkqueue_peek_data(cq, &data, &dlen, errh);
if (rc < 0) {
chunk_release(c);
return NULL;
}
buffer_string_set_length(c->mem, dlen);
chunkqueue_release_chunks(cq);
chunkqueue_append_chunk(cq, c);
return c->mem;
}