src/lib/istream-file.c

	istream-file.c revision c06f4017027263cf3a08becc551f5126409e2a83
c25356d5978632df6203437e1953bcb29e0c736fTimo Sirainen/* Copyright (c) 2002-2003 Timo Sirainen */
c25356d5978632df6203437e1953bcb29e0c736fTimo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen/* @UNSAFE: whole file */
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen#include "lib.h"
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen#include "ioloop.h"
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen#include "istream-internal.h"
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen#include "network.h"
6cc0546c058f3e6253c6f99727b28dd602712974Timo Sirainen
6cc0546c058f3e6253c6f99727b28dd602712974Timo Sirainen#include <time.h>
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen#include <unistd.h>
6cc0546c058f3e6253c6f99727b28dd602712974Timo Sirainen#include <sys/stat.h>
6cc0546c058f3e6253c6f99727b28dd602712974Timo Sirainen
6cc0546c058f3e6253c6f99727b28dd602712974Timo Sirainen#define I_STREAM_MIN_SIZE 4096
0ce5f96804e81cb0f857e7df32c0272f1eed9377Timo Sirainen
0ce5f96804e81cb0f857e7df32c0272f1eed9377Timo Sirainenstruct file_istream {
0ce5f96804e81cb0f857e7df32c0272f1eed9377Timo Sirainen    struct _istream istream;
0ce5f96804e81cb0f857e7df32c0272f1eed9377Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        struct timeval fstat_cache_stamp;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
252db51b6c0a605163326b3ea5d09e9936ca3b29Timo Sirainen    size_t max_buffer_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    uoff_t skip_left;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen    unsigned int file:1;
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen    unsigned int autoclose_fd:1;
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen};
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainenstatic void _close(struct _iostream *stream)
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen{
9b7eeffb5752b500ac62ba1fd01c4a8c4ada14e9Timo Sirainen    struct file_istream *fstream = (struct file_istream *) stream;
9b7eeffb5752b500ac62ba1fd01c4a8c4ada14e9Timo Sirainen    struct _istream *_stream = (struct _istream *) stream;
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen
93fa87cf1a96c4f279ec4f5c311820313ba12c34Timo Sirainen    if (fstream->autoclose_fd && _stream->fd != -1) {
43834f87bf431198f986e86052a4f6e558fdb07dTimo Sirainen        if (close(_stream->fd) < 0)
43834f87bf431198f986e86052a4f6e558fdb07dTimo Sirainen            i_error("file_istream.close() failed: %m");
93fa87cf1a96c4f279ec4f5c311820313ba12c34Timo Sirainen    }
93fa87cf1a96c4f279ec4f5c311820313ba12c34Timo Sirainen    _stream->fd = -1;
93fa87cf1a96c4f279ec4f5c311820313ba12c34Timo Sirainen}
93fa87cf1a96c4f279ec4f5c311820313ba12c34Timo Sirainen
43834f87bf431198f986e86052a4f6e558fdb07dTimo Sirainenstatic void _destroy(struct _iostream *stream)
b565a6a7a66fb9f224d00c06a950e3c1c585c18eTimo Sirainen{
b565a6a7a66fb9f224d00c06a950e3c1c585c18eTimo Sirainen    struct _istream *_stream = (struct _istream *) stream;
0c1835a90dd1dcedaeaedd1cd91672299cbeb5beTimo Sirainen
0c1835a90dd1dcedaeaedd1cd91672299cbeb5beTimo Sirainen    p_free(_stream->iostream.pool, _stream->w_buffer);
f4735bf7ec2019fdc730e9ebdb39e5a4ea580405Timo Sirainen}
f4735bf7ec2019fdc730e9ebdb39e5a4ea580405Timo Sirainen
f4735bf7ec2019fdc730e9ebdb39e5a4ea580405Timo Sirainenstatic void _set_max_buffer_size(struct _iostream *stream, size_t max_size)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
8cb72c59d5ea4e9e5f638d7ec840bb853f5a188eTimo Sirainen    struct file_istream *fstream = (struct file_istream *) stream;
8cb72c59d5ea4e9e5f638d7ec840bb853f5a188eTimo Sirainen
8cb72c59d5ea4e9e5f638d7ec840bb853f5a188eTimo Sirainen    fstream->max_buffer_size = max_size;
8cb72c59d5ea4e9e5f638d7ec840bb853f5a188eTimo Sirainen}
8cb72c59d5ea4e9e5f638d7ec840bb853f5a188eTimo Sirainen
8b247780e911909a9fdc47f69ce6d1478902ad98Timo Sirainenstatic void i_stream_grow_buffer(struct _istream *stream, size_t bytes)
8b247780e911909a9fdc47f69ce6d1478902ad98Timo Sirainen{
862ec874f9373e3e499e237d3b9f71fdf1413feeTimo Sirainen    struct file_istream *fstream = (struct file_istream *) stream;
862ec874f9373e3e499e237d3b9f71fdf1413feeTimo Sirainen    size_t old_size;
862ec874f9373e3e499e237d3b9f71fdf1413feeTimo Sirainen
8b247780e911909a9fdc47f69ce6d1478902ad98Timo Sirainen    old_size = stream->buffer_size;
e2ce8d4a6ac5d82a906178148453e7613fab9ba0Timo Sirainen
cd56a23e21f1df3f79648cf07e2f4385e2fadebbTimo Sirainen    stream->buffer_size = stream->pos + bytes;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (stream->buffer_size <= I_STREAM_MIN_SIZE)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->buffer_size = I_STREAM_MIN_SIZE;
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    else {
d5cebe7f98e63d4e2822863ef2faa4971e8b3a5dTimo Sirainen        stream->buffer_size =
d5cebe7f98e63d4e2822863ef2faa4971e8b3a5dTimo Sirainen            pool_get_exp_grown_size(stream->iostream.pool,
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen                        old_size, stream->buffer_size);
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen    }
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen    if (fstream->max_buffer_size > 0 &&
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen        stream->buffer_size > fstream->max_buffer_size)
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen        stream->buffer_size = fstream->max_buffer_size;
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen    stream->buffer = stream->w_buffer =
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen        p_realloc(stream->iostream.pool, stream->w_buffer,
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen              old_size, stream->buffer_size);
eb98a038ca8b0ef33d1d11794803ce09547496faTimo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
e2ce8d4a6ac5d82a906178148453e7613fab9ba0Timo Sirainenstatic void i_stream_compress(struct _istream *stream)
e2ce8d4a6ac5d82a906178148453e7613fab9ba0Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    memmove(stream->w_buffer, stream->w_buffer + stream->skip,
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->pos - stream->skip);
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen    stream->pos -= stream->skip;
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen    stream->skip = 0;
211ed7806d8715ec2280ffbf5d10f0d6e4f1beb2Timo Sirainen}
a10ed8c47534b4c6b6bf2711ccfe577e720a47b4Timo Sirainen
59151b71059df1190acd75d8717ed04a7920c862Timo Sirainenstatic ssize_t _read(struct _istream *stream)
27a44fcfd8d19bffe0f267f20a2b5d3fe7600fddTimo Sirainen{
27a44fcfd8d19bffe0f267f20a2b5d3fe7600fddTimo Sirainen    struct file_istream *fstream = (struct file_istream *) stream;
27a44fcfd8d19bffe0f267f20a2b5d3fe7600fddTimo Sirainen    size_t size;
59151b71059df1190acd75d8717ed04a7920c862Timo Sirainen    ssize_t ret;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    if (stream->istream.closed)
556f95092c3bc850517d5ab2bb502024a55645f1Timo Sirainen        return -1;
556f95092c3bc850517d5ab2bb502024a55645f1Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    stream->istream.stream_errno = 0;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen    if (stream->pos == stream->buffer_size) {
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen        if (stream->skip > 0) {
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen            /* remove the unused bytes from beginning of buffer */
10ff47d5d6146995e16da00d36eca7d162064a7bTimo Sirainen                        i_stream_compress(stream);
683eebe490bbe5caec246c535a10ea9f93f5c330Timo Sirainen        } else if (fstream->max_buffer_size == 0 ||
683eebe490bbe5caec246c535a10ea9f93f5c330Timo Sirainen               stream->buffer_size < fstream->max_buffer_size) {
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen            /* buffer is full - grow it */
5238111c460098d9cc8cc22527026138a278b9a4Timo Sirainen            i_stream_grow_buffer(stream, I_STREAM_MIN_SIZE);
5238111c460098d9cc8cc22527026138a278b9a4Timo Sirainen        }
6ef7e31619edfaa17ed044b45861d106a86191efTimo Sirainen
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen        if (stream->pos == stream->buffer_size)
68a4946b12583b88fa802e52ebee45cd96056772Timo Sirainen            return -2; /* buffer full */
de954ff15b495be13007a8aca2c09fd1d356a283Timo Sirainen    }
de954ff15b495be13007a8aca2c09fd1d356a283Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    size = stream->buffer_size - stream->pos;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    ret = -1;
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen    do {
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen        if (fstream->file) {
2767104d81e97a109f0aa9758792bfa1da325a97Timo Sirainen            ret = pread(stream->fd, stream->w_buffer + stream->pos,
0ce5f96804e81cb0f857e7df32c0272f1eed9377Timo Sirainen                    size, stream->istream.v_offset +
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen                    (stream->pos - stream->skip));
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        } else {
ceb43cc04edb94445fab8f914bc4da6d740403d1Timo Sirainen            ret = read(stream->fd, stream->w_buffer + stream->pos,
ceb43cc04edb94445fab8f914bc4da6d740403d1Timo Sirainen                   size);
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        }
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen    } while (ret < 0 && errno == EINTR && stream->istream.blocking);
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen    if (ret == 0) {
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        /* EOF */
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        stream->istream.eof = TRUE;
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        return -1;
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen    }
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen    if (ret < 0) {
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        if (errno == EINTR || errno == EAGAIN) {
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen            i_assert(!stream->istream.blocking);
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen            ret = 0;
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen        } else {
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen            stream->istream.eof = TRUE;
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen            stream->istream.stream_errno = errno;
e2a88d59c0d47d63ce1ad5b1fd95e487124a3fd4Timo Sirainen            return -1;
d77fb3be552eefbfb9cdd43ff23d794796d7a36cTimo Sirainen        }
d77fb3be552eefbfb9cdd43ff23d794796d7a36cTimo Sirainen    }
d77fb3be552eefbfb9cdd43ff23d794796d7a36cTimo Sirainen
03f5c621d06d6b6d77a145196c9633a7aa64dc78Timo Sirainen    if (ret > 0 && fstream->skip_left > 0) {
d7e72877b7a5085c3addf9729d0bfbe1b5357853Timo Sirainen        i_assert(!fstream->file);
d7e72877b7a5085c3addf9729d0bfbe1b5357853Timo Sirainen        i_assert(stream->skip == stream->pos);
d7e72877b7a5085c3addf9729d0bfbe1b5357853Timo Sirainen
d7e72877b7a5085c3addf9729d0bfbe1b5357853Timo Sirainen        if (fstream->skip_left >= (size_t)ret) {
03f5c621d06d6b6d77a145196c9633a7aa64dc78Timo Sirainen            fstream->skip_left -= ret;
03f5c621d06d6b6d77a145196c9633a7aa64dc78Timo Sirainen            ret = 0;
03f5c621d06d6b6d77a145196c9633a7aa64dc78Timo Sirainen        } else {
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen            ret -= fstream->skip_left;
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen            stream->pos += fstream->skip_left;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            stream->skip += fstream->skip_left;
8cdb3234fe3c77e477c7a0e6934678f58fc54d4dTimo Sirainen            fstream->skip_left = 0;
8cdb3234fe3c77e477c7a0e6934678f58fc54d4dTimo Sirainen        }
8cdb3234fe3c77e477c7a0e6934678f58fc54d4dTimo Sirainen    }
8cdb3234fe3c77e477c7a0e6934678f58fc54d4dTimo Sirainen
71da447014454c84828d9dface77219875554d7dTimo Sirainen    stream->pos += ret;
71da447014454c84828d9dface77219875554d7dTimo Sirainen    i_assert(ret != 0 || !fstream->file);
71da447014454c84828d9dface77219875554d7dTimo Sirainen    return ret;
71da447014454c84828d9dface77219875554d7dTimo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
static void _seek(struct _istream *stream, uoff_t v_offset,
          bool mark __attr_unused__)
{
    struct file_istream *fstream = (struct file_istream *) stream;

    if (!stream->istream.seekable) {
        if (v_offset < stream->istream.v_offset) {
            stream->istream.stream_errno = ESPIPE;
            return;
        }
        fstream->skip_left += v_offset - stream->istream.v_offset;
    }

    stream->istream.stream_errno = 0;
    stream->istream.v_offset = v_offset;
    stream->skip = stream->pos = 0;
}

static void _sync(struct _istream *stream)
{
    struct file_istream *fstream = (struct file_istream *) stream;

    fstream->fstat_cache_stamp.tv_sec = 0;

    if (!stream->istream.seekable) {
        /* can't do anything or data would be lost */
        return;
    }

    stream->skip = stream->pos = 0;
}

static int fstat_cached(struct file_istream *fstream)
{
    if (fstream->fstat_cache_stamp.tv_sec == ioloop_timeval.tv_sec &&
        fstream->fstat_cache_stamp.tv_usec == ioloop_timeval.tv_usec)
        return 0;

    if (fstat(fstream->istream.fd, &fstream->istream.statbuf) < 0) {
        i_error("file_istream.fstat() failed: %m");
        return -1;
    }

    fstream->fstat_cache_stamp = ioloop_timeval;
    return 0;
}

static const struct stat *
_stat(struct _istream *stream, bool exact __attr_unused__)
{
    struct file_istream *fstream = (struct file_istream *) stream;

    if (fstream->file) {
        if (fstat_cached(fstream) < 0)
            return NULL;
    }

    return &stream->statbuf;
}

struct istream *i_stream_create_file(int fd, pool_t pool,
                     size_t max_buffer_size, bool autoclose_fd)
{
    struct file_istream *fstream;
    struct stat st;

    fstream = p_new(pool, struct file_istream, 1);
    fstream->max_buffer_size = max_buffer_size;
    fstream->autoclose_fd = autoclose_fd;

    fstream->istream.iostream.close = _close;
    fstream->istream.iostream.destroy = _destroy;
    fstream->istream.iostream.set_max_buffer_size = _set_max_buffer_size;

    fstream->istream.read = _read;
    fstream->istream.seek = _seek;
    fstream->istream.sync = _sync;
    fstream->istream.stat = _stat;

    /* if it's a file, set the flags properly */
    if (fstat(fd, &st) == 0 && S_ISREG(st.st_mode)) {
        fstream->file = TRUE;
        fstream->istream.istream.blocking = TRUE;
        fstream->istream.istream.seekable = TRUE;
    }

    return _i_stream_create(&fstream->istream, pool, fd, 0);
}