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This commit is contained in:
Konstantin Knizhnik 2019-02-01 20:00:03 +03:00
parent 62c2028a0f
commit 9c27c4d928
1 changed files with 39 additions and 22 deletions
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61
src/utils/file.c
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@ -384,6 +384,12 @@ int fio_truncate(int fd, off_t size)
}
}
/*
* Read file from specified location.
* This call is optimized for delat backup, to avoid trasfer of old pages to backup host.
* For delta backup horizon_lsn parameter is assigned value of last backup and for all pages with LSN smaller than horizon_lsn only page header is sent.
*/
int fio_pread(FILE* f, void* buf, off_t offs, XLogRecPtr horizon_lsn)
{
if (fio_is_remote_file(f))
@ -405,11 +411,16 @@ int fio_pread(FILE* f, void* buf, off_t offs, XLogRecPtr horizon_lsn)
if (hdr.size != 0)
IO_CHECK(fio_read_all(fio_stdin, buf, hdr.size), hdr.size);
/*
* We either return <0 for error, either 0 for EOF, either received size (page or page header size)
* for fully read page either 1 for partly read page. 1 is used just to distinguish it with page header size.
*/
return hdr.arg <= 0 ? hdr.arg : hdr.arg == BLCKSZ ? hdr.size : 1;
}
else
{
int rc = pread(fileno(f), buf, BLCKSZ, offs);
/* See comment above consernign returned value */
return rc <= 0 || rc == BLCKSZ ? rc : 1;
}
}
@ -796,6 +807,11 @@ static void fio_send_file(int out, char const* path)
/* Execute commands at remote host */
void fio_communicate(int in, int out)
{
/*
* Map of file and directory descriptors.
* The same mapping is used in agent and master process, so we
* can use the same index at both sides.
*/
int fd[FIO_FDMAX];
DIR* dir[FIO_FDMAX];
struct dirent* entry;
@ -806,22 +822,24 @@ void fio_communicate(int in, int out)
XLogRecPtr horizon_lsn;
int rc;
/* Main loop until command of processing master command */
while ((rc = fio_read_all(in, &hdr, sizeof hdr)) == sizeof(hdr)) {
if (hdr.size != 0) {
if (hdr.size > buf_size) {
/* Extend buffer on demand */
buf_size = hdr.size;
buf = (char*)realloc(buf, buf_size);
}
IO_CHECK(fio_read_all(in, buf, hdr.size), hdr.size);
}
switch (hdr.cop) {
case FIO_LOAD:
case FIO_LOAD: /* Send file content */
fio_send_file(out, buf);
break;
case FIO_OPENDIR:
case FIO_OPENDIR: /* Open directory for traversal */
dir[hdr.handle] = opendir(buf);
break;
case FIO_READDIR:
case FIO_READDIR: /* Get next direcrtory entry */
entry = readdir(dir[hdr.handle]);
hdr.cop = FIO_SEND;
if (entry != NULL) {
@ -833,20 +851,19 @@ void fio_communicate(int in, int out)
IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
}
break;
case FIO_CLOSEDIR:
case FIO_CLOSEDIR: /* Finish directory traversal */
SYS_CHECK(closedir(dir[hdr.handle]));
break;
case FIO_OPEN:
case FIO_OPEN: /* Open file */
SYS_CHECK(fd[hdr.handle] = open(buf, hdr.arg, FILE_PERMISSIONS));
fprintf(stderr, "Open file %s -> %d\n", buf, hdr.handle);
break;
case FIO_CLOSE:
case FIO_CLOSE: /* Close file */
SYS_CHECK(close(fd[hdr.handle]));
break;
case FIO_WRITE:
case FIO_WRITE: /* Write to the current position in file */
IO_CHECK(fio_write_all(fd[hdr.handle], buf, hdr.size), hdr.size);
break;
case FIO_READ:
case FIO_READ: /* Read from the current position in file */
if ((size_t)hdr.arg > buf_size) {
buf_size = hdr.arg;
buf = (char*)realloc(buf, buf_size);
@ -857,53 +874,53 @@ void fio_communicate(int in, int out)
IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
IO_CHECK(fio_write_all(out, buf, hdr.size), hdr.size);
break;
case FIO_PREAD:
case FIO_PREAD: /* Read from specified position in file, ignoring pages beyond horizon of delta backup */
horizon_lsn = *(XLogRecPtr*)buf;
rc = pread(fd[hdr.handle], buf, BLCKSZ, hdr.arg);
fprintf(stderr, "Read %d bytes from file %d offset %d\n", rc, hdr.handle, hdr.arg);
hdr.cop = FIO_SEND;
hdr.arg = rc;
/* For pages beyond horizon of delta backup transfer only page header */
hdr.size = (rc == BLCKSZ)
? PageXLogRecPtrGet(((PageHeader)buf)->pd_lsn) < horizon_lsn
? PageXLogRecPtrGet(((PageHeader)buf)->pd_lsn) < horizon_lsn /* For non-delta backup horizon_lsn == 0, so this condition is always false */
? sizeof(PageHeaderData) : BLCKSZ
: 0;
IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
if (hdr.size != 0)
IO_CHECK(fio_write_all(out, buf, hdr.size), hdr.size);
break;
case FIO_FSTAT:
case FIO_FSTAT: /* Get information about opened file */
hdr.size = sizeof(st);
hdr.arg = fstat(fd[hdr.handle], &st);
IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
IO_CHECK(fio_write_all(out, &st, sizeof(st)), sizeof(st));
break;
case FIO_STAT:
case FIO_STAT: /* Get information about file with specified path */
hdr.size = sizeof(st);
hdr.arg = hdr.arg ? stat(buf, &st) : lstat(buf, &st);
IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
IO_CHECK(fio_write_all(out, &st, sizeof(st)), sizeof(st));
break;
case FIO_ACCESS:
case FIO_ACCESS: /* Check presence of file with specified name */
hdr.size = 0;
hdr.arg = access(buf, hdr.arg);
IO_CHECK(fio_write_all(out, &hdr, sizeof(hdr)), sizeof(hdr));
break;
case FIO_RENAME:
case FIO_RENAME: /* Rename file */
SYS_CHECK(rename(buf, buf + strlen(buf) + 1));
break;
case FIO_UNLINK:
case FIO_UNLINK: /* Remove file or directory (TODO: Win32) */
SYS_CHECK(remove(buf));
break;
case FIO_MKDIR:
case FIO_MKDIR: /* Create direcory */
SYS_CHECK(dir_create_dir(buf, hdr.arg));
break;
case FIO_CHMOD:
case FIO_CHMOD: /* Change file mode */
SYS_CHECK(chmod(buf, hdr.arg));
break;
case FIO_SEEK:
case FIO_SEEK: /* Set current position in file */
SYS_CHECK(lseek(fd[hdr.handle], hdr.arg, SEEK_SET));
break;
case FIO_TRUNCATE:
case FIO_TRUNCATE: /* Truncate file */
SYS_CHECK(ftruncate(fd[hdr.handle], hdr.arg));
break;
default:
@ -911,7 +928,7 @@ void fio_communicate(int in, int out)
}
}
free(buf);
if (rc != 0) {
if (rc != 0) { /* Not end of stream: normal pipe close */
perror("read");
exit(EXIT_FAILURE);
}