[thirdparty/systemd.git] / src / import / export-raw.c

/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <sys/sendfile.h>

#include "sd-daemon.h"
#include "sd-event.h"

#include "alloc-util.h"
#include "copy.h"
#include "export-raw.h"
#include "fd-util.h"
#include "format-util.h"
#include "fs-util.h"
#include "log.h"
#include "pretty-print.h"
#include "ratelimit.h"
#include "stat-util.h"
#include "string-util.h"
#include "terminal-util.h"
#include "time-util.h"
#include "tmpfile-util.h"

#define COPY_BUFFER_SIZE (16*1024)

typedef struct RawExport {
        sd_event *event;

        RawExportFinished on_finished;
        void *userdata;

        char *path;

        int input_fd;
        int output_fd;

        ImportCompress compress;

        sd_event_source *output_event_source;

        void *buffer;
        size_t buffer_size;
        size_t buffer_allocated;

        uint64_t written_compressed;
        uint64_t written_uncompressed;

        unsigned last_percent;
        RateLimit progress_ratelimit;

        struct stat st;

        bool eof;
        bool tried_reflink;
        bool tried_sendfile;
} RawExport;

RawExport *raw_export_unref(RawExport *e) {
        if (!e)
                return NULL;

        sd_event_source_unref(e->output_event_source);

        import_compress_free(&e->compress);

        sd_event_unref(e->event);

        safe_close(e->input_fd);

        free(e->buffer);
        free(e->path);
        return mfree(e);
}

int raw_export_new(
                RawExport **ret,
                sd_event *event,
                RawExportFinished on_finished,
                void *userdata) {

        _cleanup_(raw_export_unrefp) RawExport *e = NULL;
        int r;

        assert(ret);

        e = new(RawExport, 1);
        if (!e)
                return -ENOMEM;

        *e = (RawExport) {
                .output_fd = -EBADF,
                .input_fd = -EBADF,
                .on_finished = on_finished,
                .userdata = userdata,
                .last_percent = UINT_MAX,
                .progress_ratelimit = { 100 * USEC_PER_MSEC, 1 },
        };

        if (event)
                e->event = sd_event_ref(event);
        else {
                r = sd_event_default(&e->event);
                if (r < 0)
                        return r;
        }

        *ret = TAKE_PTR(e);

        return 0;
}

static void raw_export_report_progress(RawExport *e) {
        unsigned percent;
        assert(e);

        if (e->written_uncompressed >= (uint64_t) e->st.st_size)
                percent = 100;
        else
                percent = (unsigned) ((e->written_uncompressed * UINT64_C(100)) / (uint64_t) e->st.st_size);

        if (percent == e->last_percent)
                return;

        if (!ratelimit_below(&e->progress_ratelimit))
                return;

        sd_notifyf(false, "X_IMPORT_PROGRESS=%u%%", percent);

        if (isatty_safe(STDERR_FILENO))
                (void) draw_progress_barf(
                                percent,
                                "%s %s/%s",
                                glyph(GLYPH_ARROW_RIGHT),
                                FORMAT_BYTES(e->written_uncompressed),
                                FORMAT_BYTES(e->st.st_size));
        else
                log_info("Exported %u%%.", percent);

        e->last_percent = percent;
}

static int raw_export_process(RawExport *e) {
        ssize_t l;
        int r;

        assert(e);

        if (!e->tried_reflink && e->compress.type == IMPORT_COMPRESS_UNCOMPRESSED) {

                /* If we shall take an uncompressed snapshot we can
                 * reflink source to destination directly. Let's see
                 * if this works. */

                r = reflink(e->input_fd, e->output_fd);
                if (r >= 0) {
                        r = 0;
                        goto finish;
                }

                e->tried_reflink = true;
        }

        if (!e->tried_sendfile && e->compress.type == IMPORT_COMPRESS_UNCOMPRESSED) {

                l = sendfile(e->output_fd, e->input_fd, NULL, COPY_BUFFER_SIZE);
                if (l < 0) {
                        if (errno == EAGAIN)
                                return 0;

                        e->tried_sendfile = true;
                } else if (l == 0) {
                        r = 0;
                        goto finish;
                } else {
                        e->written_uncompressed += l;
                        e->written_compressed += l;

                        raw_export_report_progress(e);

                        return 0;
                }
        }

        while (e->buffer_size <= 0) {
                uint8_t input[COPY_BUFFER_SIZE];

                if (e->eof) {
                        r = 0;
                        goto finish;
                }

                l = read(e->input_fd, input, sizeof(input));
                if (l < 0) {
                        r = log_error_errno(errno, "Failed to read raw file: %m");
                        goto finish;
                }

                if (l == 0) {
                        e->eof = true;
                        r = import_compress_finish(&e->compress, &e->buffer, &e->buffer_size, &e->buffer_allocated);
                } else {
                        e->written_uncompressed += l;
                        r = import_compress(&e->compress, input, l, &e->buffer, &e->buffer_size, &e->buffer_allocated);
                }
                if (r < 0) {
                        r = log_error_errno(r, "Failed to encode: %m");
                        goto finish;
                }
        }

        l = write(e->output_fd, e->buffer, e->buffer_size);
        if (l < 0) {
                if (errno == EAGAIN)
                        return 0;

                r = log_error_errno(errno, "Failed to write output file: %m");
                goto finish;
        }

        assert((size_t) l <= e->buffer_size);
        memmove(e->buffer, (uint8_t*) e->buffer + l, e->buffer_size - l);
        e->buffer_size -= l;
        e->written_compressed += l;

        raw_export_report_progress(e);

        return 0;

finish:
        if (r >= 0) {
                if (isatty_safe(STDERR_FILENO))
                        clear_progress_bar(/* prefix= */ NULL);

                (void) copy_times(e->input_fd, e->output_fd, COPY_CRTIME);
                (void) copy_xattr(e->input_fd, NULL, e->output_fd, NULL, 0);
        }

        if (e->on_finished)
                e->on_finished(e, r, e->userdata);
        else
                sd_event_exit(e->event, r);

        return 0;
}

static int raw_export_on_output(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
        RawExport *i = userdata;

        return raw_export_process(i);
}

static int raw_export_on_defer(sd_event_source *s, void *userdata) {
        RawExport *i = userdata;

        return raw_export_process(i);
}

static int reflink_snapshot(int fd, const char *path) {
        int new_fd, r;

        new_fd = open_parent(path, O_TMPFILE|O_CLOEXEC|O_RDWR, 0600);
        if (new_fd < 0) {
                _cleanup_free_ char *t = NULL;

                r = tempfn_random(path, NULL, &t);
                if (r < 0)
                        return r;

                new_fd = open(t, O_CLOEXEC|O_CREAT|O_NOCTTY|O_RDWR, 0600);
                if (new_fd < 0)
                        return -errno;

                (void) unlink(t);
        }

        r = reflink(fd, new_fd);
        if (r < 0) {
                safe_close(new_fd);
                return r;
        }

        return new_fd;
}

int raw_export_start(RawExport *e, const char *path, int fd, ImportCompressType compress) {
        _cleanup_close_ int sfd = -EBADF, tfd = -EBADF;
        int r;

        assert(e);
        assert(path);
        assert(fd >= 0);
        assert(compress < _IMPORT_COMPRESS_TYPE_MAX);
        assert(compress != IMPORT_COMPRESS_UNKNOWN);

        if (e->output_fd >= 0)
                return -EBUSY;

        r = fd_nonblock(fd, true);
        if (r < 0)
                return r;

        r = free_and_strdup(&e->path, path);
        if (r < 0)
                return r;

        sfd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY);
        if (sfd < 0)
                return -errno;

        if (fstat(sfd, &e->st) < 0)
                return -errno;
        r = stat_verify_regular(&e->st);
        if (r < 0)
                return r;

        /* Try to take a reflink snapshot of the file, if we can t make the export atomic */
        tfd = reflink_snapshot(sfd, path);
        if (tfd >= 0)
                e->input_fd = TAKE_FD(tfd);
        else
                e->input_fd = TAKE_FD(sfd);

        r = import_compress_init(&e->compress, compress);
        if (r < 0)
                return r;

        r = sd_event_add_io(e->event, &e->output_event_source, fd, EPOLLOUT, raw_export_on_output, e);
        if (r == -EPERM) {
                r = sd_event_add_defer(e->event, &e->output_event_source, raw_export_on_defer, e);
                if (r < 0)
                        return r;

                r = sd_event_source_set_enabled(e->output_event_source, SD_EVENT_ON);
        }
        if (r < 0)
                return r;

        e->output_fd = fd;
        return r;
}
Commit	Line	Data
	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
	2
	3	#include <sys/sendfile.h>
	4
	5	#include "sd-daemon.h"
	6	#include "sd-event.h"
	7
	8	#include "alloc-util.h"
	9	#include "copy.h"
	10	#include "export-raw.h"
	11	#include "fd-util.h"
	12	#include "format-util.h"
	13	#include "fs-util.h"
	14	#include "log.h"
	15	#include "pretty-print.h"
	16	#include "ratelimit.h"
	17	#include "stat-util.h"
	18	#include "string-util.h"
	19	#include "terminal-util.h"
	20	#include "time-util.h"
	21	#include "tmpfile-util.h"
	22
	23	#define COPY_BUFFER_SIZE (16*1024)
	24
	25	typedef struct RawExport {
	26	sd_event *event;
	27
	28	RawExportFinished on_finished;
	29	void *userdata;
	30
	31	char *path;
	32
	33	int input_fd;
	34	int output_fd;
	35
	36	ImportCompress compress;
	37
	38	sd_event_source *output_event_source;
	39
	40	void *buffer;
	41	size_t buffer_size;
	42	size_t buffer_allocated;
	43
	44	uint64_t written_compressed;
	45	uint64_t written_uncompressed;
	46
	47	unsigned last_percent;
	48	RateLimit progress_ratelimit;
	49
	50	struct stat st;
	51
	52	bool eof;
	53	bool tried_reflink;
	54	bool tried_sendfile;
	55	} RawExport;
	56
	57	RawExport raw_export_unref(RawExport e) {
	58	if (!e)
	59	return NULL;
	60
	61	sd_event_source_unref(e->output_event_source);
	62
	63	import_compress_free(&e->compress);
	64
	65	sd_event_unref(e->event);
	66
	67	safe_close(e->input_fd);
	68
	69	free(e->buffer);
	70	free(e->path);
	71	return mfree(e);
	72	}
	73
	74	int raw_export_new(
	75	RawExport **ret,
	76	sd_event *event,
	77	RawExportFinished on_finished,
	78	void *userdata) {
	79
	80	_cleanup_(raw_export_unrefp) RawExport *e = NULL;
	81	int r;
	82
	83	assert(ret);
	84
	85	e = new(RawExport, 1);
	86	if (!e)
	87	return -ENOMEM;
	88
	89	*e = (RawExport) {
	90	.output_fd = -EBADF,
	91	.input_fd = -EBADF,
	92	.on_finished = on_finished,
	93	.userdata = userdata,
	94	.last_percent = UINT_MAX,
	95	.progress_ratelimit = { 100 * USEC_PER_MSEC, 1 },
	96	};
	97
	98	if (event)
	99	e->event = sd_event_ref(event);
	100	else {
	101	r = sd_event_default(&e->event);
	102	if (r < 0)
	103	return r;
	104	}
	105
	106	*ret = TAKE_PTR(e);
	107
	108	return 0;
	109	}
	110
	111	static void raw_export_report_progress(RawExport *e) {
	112	unsigned percent;
	113	assert(e);
	114
	115	if (e->written_uncompressed >= (uint64_t) e->st.st_size)
	116	percent = 100;
	117	else
	118	percent = (unsigned) ((e->written_uncompressed * UINT64_C(100)) / (uint64_t) e->st.st_size);
	119
	120	if (percent == e->last_percent)
	121	return;
	122
	123	if (!ratelimit_below(&e->progress_ratelimit))
	124	return;
	125
	126	sd_notifyf(false, "X_IMPORT_PROGRESS=%u%%", percent);
	127
	128	if (isatty_safe(STDERR_FILENO))
	129	(void) draw_progress_barf(
	130	percent,
	131	"%s %s/%s",
	132	glyph(GLYPH_ARROW_RIGHT),
	133	FORMAT_BYTES(e->written_uncompressed),
	134	FORMAT_BYTES(e->st.st_size));
	135	else
	136	log_info("Exported %u%%.", percent);
	137
	138	e->last_percent = percent;
	139	}
	140
	141	static int raw_export_process(RawExport *e) {
	142	ssize_t l;
	143	int r;
	144
	145	assert(e);
	146
	147	if (!e->tried_reflink && e->compress.type == IMPORT_COMPRESS_UNCOMPRESSED) {
	148
	149	/* If we shall take an uncompressed snapshot we can
	150	* reflink source to destination directly. Let's see
	151	* if this works. */
	152
	153	r = reflink(e->input_fd, e->output_fd);
	154	if (r >= 0) {
	155	r = 0;
	156	goto finish;
	157	}
	158
	159	e->tried_reflink = true;
	160	}
	161
	162	if (!e->tried_sendfile && e->compress.type == IMPORT_COMPRESS_UNCOMPRESSED) {
	163
	164	l = sendfile(e->output_fd, e->input_fd, NULL, COPY_BUFFER_SIZE);
	165	if (l < 0) {
	166	if (errno == EAGAIN)
	167	return 0;
	168
	169	e->tried_sendfile = true;
	170	} else if (l == 0) {
	171	r = 0;
	172	goto finish;
	173	} else {
	174	e->written_uncompressed += l;
	175	e->written_compressed += l;
	176
	177	raw_export_report_progress(e);
	178
	179	return 0;
	180	}
	181	}
	182
	183	while (e->buffer_size <= 0) {
	184	uint8_t input[COPY_BUFFER_SIZE];
	185
	186	if (e->eof) {
	187	r = 0;
	188	goto finish;
	189	}
	190
	191	l = read(e->input_fd, input, sizeof(input));
	192	if (l < 0) {
	193	r = log_error_errno(errno, "Failed to read raw file: %m");
	194	goto finish;
	195	}
	196
	197	if (l == 0) {
	198	e->eof = true;
	199	r = import_compress_finish(&e->compress, &e->buffer, &e->buffer_size, &e->buffer_allocated);
	200	} else {
	201	e->written_uncompressed += l;
	202	r = import_compress(&e->compress, input, l, &e->buffer, &e->buffer_size, &e->buffer_allocated);
	203	}
	204	if (r < 0) {
	205	r = log_error_errno(r, "Failed to encode: %m");
	206	goto finish;
	207	}
	208	}
	209
	210	l = write(e->output_fd, e->buffer, e->buffer_size);
	211	if (l < 0) {
	212	if (errno == EAGAIN)
	213	return 0;
	214
	215	r = log_error_errno(errno, "Failed to write output file: %m");
	216	goto finish;
	217	}
	218
	219	assert((size_t) l <= e->buffer_size);
	220	memmove(e->buffer, (uint8_t*) e->buffer + l, e->buffer_size - l);
	221	e->buffer_size -= l;
	222	e->written_compressed += l;
	223
	224	raw_export_report_progress(e);
	225
	226	return 0;
	227
	228	finish:
	229	if (r >= 0) {
	230	if (isatty_safe(STDERR_FILENO))
	231	clear_progress_bar(/* prefix= */ NULL);
	232
	233	(void) copy_times(e->input_fd, e->output_fd, COPY_CRTIME);
	234	(void) copy_xattr(e->input_fd, NULL, e->output_fd, NULL, 0);
	235	}
	236
	237	if (e->on_finished)
	238	e->on_finished(e, r, e->userdata);
	239	else
	240	sd_event_exit(e->event, r);
	241
	242	return 0;
	243	}
	244
	245	static int raw_export_on_output(sd_event_source s, int fd, uint32_t revents, void userdata) {
	246	RawExport *i = userdata;
	247
	248	return raw_export_process(i);
	249	}
	250
	251	static int raw_export_on_defer(sd_event_source s, void userdata) {
	252	RawExport *i = userdata;
	253
	254	return raw_export_process(i);
	255	}
	256
	257	static int reflink_snapshot(int fd, const char *path) {
	258	int new_fd, r;
	259
	260	new_fd = open_parent(path, O_TMPFILE\|O_CLOEXEC\|O_RDWR, 0600);
	261	if (new_fd < 0) {
	262	_cleanup_free_ char *t = NULL;
	263
	264	r = tempfn_random(path, NULL, &t);
	265	if (r < 0)
	266	return r;
	267
	268	new_fd = open(t, O_CLOEXEC\|O_CREAT\|O_NOCTTY\|O_RDWR, 0600);
	269	if (new_fd < 0)
	270	return -errno;
	271
	272	(void) unlink(t);
	273	}
	274
	275	r = reflink(fd, new_fd);
	276	if (r < 0) {
	277	safe_close(new_fd);
	278	return r;
	279	}
	280
	281	return new_fd;
	282	}
	283
	284	int raw_export_start(RawExport e, const char path, int fd, ImportCompressType compress) {
	285	_cleanup_close_ int sfd = -EBADF, tfd = -EBADF;
	286	int r;
	287
	288	assert(e);
	289	assert(path);
	290	assert(fd >= 0);
	291	assert(compress < _IMPORT_COMPRESS_TYPE_MAX);
	292	assert(compress != IMPORT_COMPRESS_UNKNOWN);
	293
	294	if (e->output_fd >= 0)
	295	return -EBUSY;
	296
	297	r = fd_nonblock(fd, true);
	298	if (r < 0)
	299	return r;
	300
	301	r = free_and_strdup(&e->path, path);
	302	if (r < 0)
	303	return r;
	304
	305	sfd = open(path, O_RDONLY\|O_CLOEXEC\|O_NOCTTY);
	306	if (sfd < 0)
	307	return -errno;
	308
	309	if (fstat(sfd, &e->st) < 0)
	310	return -errno;
	311	r = stat_verify_regular(&e->st);
	312	if (r < 0)
	313	return r;
	314
	315	/* Try to take a reflink snapshot of the file, if we can t make the export atomic */
	316	tfd = reflink_snapshot(sfd, path);
	317	if (tfd >= 0)
	318	e->input_fd = TAKE_FD(tfd);
	319	else
	320	e->input_fd = TAKE_FD(sfd);
	321
	322	r = import_compress_init(&e->compress, compress);
	323	if (r < 0)
	324	return r;
	325
	326	r = sd_event_add_io(e->event, &e->output_event_source, fd, EPOLLOUT, raw_export_on_output, e);
	327	if (r == -EPERM) {
	328	r = sd_event_add_defer(e->event, &e->output_event_source, raw_export_on_defer, e);
	329	if (r < 0)
	330	return r;
	331
	332	r = sd_event_source_set_enabled(e->output_event_source, SD_EVENT_ON);
	333	}
	334	if (r < 0)
	335	return r;
	336
	337	e->output_fd = fd;
	338	return r;
	339	}