astreamer_file.c File Reference

#include "postgres_fe.h"
#include <unistd.h>
#include "common/file_perm.h"
#include "common/logging.h"
#include "common/string.h"
#include "fe_utils/astreamer.h"

Include dependency graph for astreamer_file.c:

Go to the source code of this file.

Data Structures
struct	astreamer_plain_writer
struct	astreamer_extractor

Typedefs
typedef struct astreamer_plain_writer	astreamer_plain_writer
typedef struct astreamer_extractor	astreamer_extractor

Functions
static void	astreamer_plain_writer_content (astreamer *streamer, astreamer_member *member, const char *data, int len, astreamer_archive_context context)
static void	astreamer_plain_writer_finalize (astreamer *streamer)
static void	astreamer_plain_writer_free (astreamer *streamer)
static void	astreamer_extractor_content (astreamer *streamer, astreamer_member *member, const char *data, int len, astreamer_archive_context context)
static void	astreamer_extractor_finalize (astreamer *streamer)
static void	astreamer_extractor_free (astreamer *streamer)
static void	extract_directory (const char *filename, mode_t mode)
static void	extract_link (const char *filename, const char *linktarget)
static FILE *	create_file_for_extract (const char *filename, mode_t mode)
astreamer *	astreamer_plain_writer_new (char *pathname, FILE *file)
astreamer *	astreamer_extractor_new (const char *basepath, const char *(*link_map)(const char *), void(*report_output_file)(const char *))
static bool	should_allow_existing_directory (const char *pathname)

Variables
static const astreamer_ops	astreamer_plain_writer_ops
static const astreamer_ops	astreamer_extractor_ops

Typedef Documentation

astreamer_extractor

typedef struct astreamer_extractor astreamer_extractor

astreamer_plain_writer

typedef struct astreamer_plain_writer astreamer_plain_writer

Function Documentation

astreamer_extractor_content()

static void astreamer_extractor_content ( astreamer *  streamer, astreamer_member *  member, const char *  data, int  len, astreamer_archive_context  context  )

static

Definition at line 207 of file astreamer_file.c.

{
    astreamer_extractor *mystreamer = (astreamer_extractor *) streamer;
    int         fnamelen;
 
    Assert(member != NULL || context == ASTREAMER_ARCHIVE_TRAILER);
    Assert(context != ASTREAMER_UNKNOWN);
 
    switch (context)
    {
        case ASTREAMER_MEMBER_HEADER:
            Assert(mystreamer->file == NULL);
 
            /* Prepend basepath. */
            snprintf(mystreamer->filename, sizeof(mystreamer->filename),
                     "%s/%s", mystreamer->basepath, member->pathname);
 
            /* Remove any trailing slash. */
            fnamelen = strlen(mystreamer->filename);
            if (mystreamer->filename[fnamelen - 1] == '/')
                mystreamer->filename[fnamelen - 1] = '\0';
 
            /* Dispatch based on file type. */
            if (member->is_directory)
                extract_directory(mystreamer->filename, member->mode);
            else if (member->is_link)
            {
                const char *linktarget = member->linktarget;
 
                if (mystreamer->link_map)
                    linktarget = mystreamer->link_map(linktarget);
                extract_link(mystreamer->filename, linktarget);
            }
            else
                mystreamer->file =
                    create_file_for_extract(mystreamer->filename,
                                            member->mode);
 
            /* Report output file change. */
            if (mystreamer->report_output_file)
                mystreamer->report_output_file(mystreamer->filename);
            break;
 
        case ASTREAMER_MEMBER_CONTENTS:
            if (mystreamer->file == NULL)
                break;
 
            errno = 0;
            if (len > 0 && fwrite(data, len, 1, mystreamer->file) != 1)
            {
                /* if write didn't set errno, assume problem is no disk space */
                if (errno == 0)
                    errno = ENOSPC;
                pg_fatal("could not write to file \"%s\": %m",
                         mystreamer->filename);
            }
            break;
 
        case ASTREAMER_MEMBER_TRAILER:
            if (mystreamer->file == NULL)
                break;
            fclose(mystreamer->file);
            mystreamer->file = NULL;
            break;
 
        case ASTREAMER_ARCHIVE_TRAILER:
            break;
 
        default:
            /* Shouldn't happen. */
            pg_fatal("unexpected state while extracting archive");
    }
}

References Assert, ASTREAMER_ARCHIVE_TRAILER, ASTREAMER_MEMBER_CONTENTS, ASTREAMER_MEMBER_HEADER, ASTREAMER_MEMBER_TRAILER, ASTREAMER_UNKNOWN, astreamer_extractor::basepath, context, create_file_for_extract(), data, extract_directory(), extract_link(), astreamer_extractor::file, astreamer_extractor::filename, astreamer_member::is_directory, astreamer_member::is_link, len, astreamer_extractor::link_map, astreamer_member::linktarget, astreamer_member::mode, astreamer_member::pathname, pg_fatal, astreamer_extractor::report_output_file, and snprintf.

astreamer_extractor_finalize()

static void astreamer_extractor_finalize ( astreamer *  streamer )

static

Definition at line 382 of file astreamer_file.c.

{
    astreamer_extractor *mystreamer PG_USED_FOR_ASSERTS_ONLY
    = (astreamer_extractor *) streamer;
 
    Assert(mystreamer->file == NULL);
}

References Assert, and PG_USED_FOR_ASSERTS_ONLY.

astreamer_extractor_free()

static void astreamer_extractor_free ( astreamer *  streamer )

static

Definition at line 394 of file astreamer_file.c.

{
    astreamer_extractor *mystreamer = (astreamer_extractor *) streamer;
 
    pfree(mystreamer->basepath);
    pfree(mystreamer);
}

References astreamer_extractor::basepath, and pfree().

astreamer_extractor_new()

astreamer* astreamer_extractor_new	(	const char *	basepath,
		const char *(*)(const char *)	link_map,
		void(*)(const char *)	report_output_file
	)

Definition at line 187 of file astreamer_file.c.

{
    astreamer_extractor *streamer;
 
    streamer = palloc0(sizeof(astreamer_extractor));
    *((const astreamer_ops **) &streamer->base.bbs_ops) =
        &astreamer_extractor_ops;
    streamer->basepath = pstrdup(basepath);
    streamer->link_map = link_map;
    streamer->report_output_file = report_output_file;
 
    return &streamer->base;
}

References astreamer_extractor_ops, astreamer_extractor::base, astreamer_extractor::basepath, astreamer::bbs_ops, astreamer_extractor::link_map, palloc0(), pstrdup(), and astreamer_extractor::report_output_file.

Referenced by CreateBackupStreamer().

astreamer_plain_writer_content()

static void astreamer_plain_writer_content ( astreamer *  streamer, astreamer_member *  member, const char *  data, int  len, astreamer_archive_context  context  )

static

Definition at line 108 of file astreamer_file.c.

{
    astreamer_plain_writer *mystreamer;
 
    mystreamer = (astreamer_plain_writer *) streamer;
 
    if (len == 0)
        return;
 
    errno = 0;
    if (fwrite(data, len, 1, mystreamer->file) != 1)
    {
        /* if write didn't set errno, assume problem is no disk space */
        if (errno == 0)
            errno = ENOSPC;
        pg_fatal("could not write to file \"%s\": %m",
                 mystreamer->pathname);
    }
}

References data, astreamer_plain_writer::file, len, astreamer_plain_writer::pathname, and pg_fatal.

astreamer_plain_writer_finalize()

static void astreamer_plain_writer_finalize ( astreamer *  streamer )

static

Definition at line 135 of file astreamer_file.c.

{
    astreamer_plain_writer *mystreamer;
 
    mystreamer = (astreamer_plain_writer *) streamer;
 
    if (mystreamer->should_close_file && fclose(mystreamer->file) != 0)
        pg_fatal("could not close file \"%s\": %m",
                 mystreamer->pathname);
 
    mystreamer->file = NULL;
    mystreamer->should_close_file = false;
}

References astreamer_plain_writer::file, astreamer_plain_writer::pathname, pg_fatal, and astreamer_plain_writer::should_close_file.

astreamer_plain_writer_free()

static void astreamer_plain_writer_free ( astreamer *  streamer )

static

Definition at line 153 of file astreamer_file.c.

{
    astreamer_plain_writer *mystreamer;
 
    mystreamer = (astreamer_plain_writer *) streamer;
 
    Assert(!mystreamer->should_close_file);
    Assert(mystreamer->base.bbs_next == NULL);
 
    pfree(mystreamer->pathname);
    pfree(mystreamer);
}

References Assert, astreamer_plain_writer::base, astreamer::bbs_next, astreamer_plain_writer::pathname, pfree(), and astreamer_plain_writer::should_close_file.

astreamer_plain_writer_new()

astreamer* astreamer_plain_writer_new	(	char *	pathname,
		FILE *	file
	)

Definition at line 82 of file astreamer_file.c.

{
    astreamer_plain_writer *streamer;
 
    streamer = palloc0(sizeof(astreamer_plain_writer));
    *((const astreamer_ops **) &streamer->base.bbs_ops) =
        &astreamer_plain_writer_ops;
 
    streamer->pathname = pstrdup(pathname);
    streamer->file = file;
 
    if (file == NULL)
    {
        streamer->file = fopen(pathname, "wb");
        if (streamer->file == NULL)
            pg_fatal("could not create file \"%s\": %m", pathname);
        streamer->should_close_file = true;
    }
 
    return &streamer->base;
}

References astreamer_plain_writer_ops, astreamer_plain_writer::base, astreamer::bbs_ops, astreamer_plain_writer::file, palloc0(), astreamer_plain_writer::pathname, pg_fatal, pstrdup(), and astreamer_plain_writer::should_close_file.

Referenced by CreateBackupStreamer().

create_file_for_extract()

static FILE * create_file_for_extract ( const char *  filename, mode_t  mode  )

static

Definition at line 359 of file astreamer_file.c.

{
    FILE       *file;
 
    file = fopen(filename, "wb");
    if (file == NULL)
        pg_fatal("could not create file \"%s\": %m", filename);
 
#ifndef WIN32
    if (chmod(filename, mode))
        pg_fatal("could not set permissions on file \"%s\": %m",
                 filename);
#endif
 
    return file;
}

References filename, mode, and pg_fatal.

Referenced by astreamer_extractor_content().

extract_directory()

static void extract_directory ( const char *  filename, mode_t  mode  )

static

Definition at line 321 of file astreamer_file.c.

{
    if (mkdir(filename, pg_dir_create_mode) != 0 &&
        (errno != EEXIST || !should_allow_existing_directory(filename)))
        pg_fatal("could not create directory \"%s\": %m",
                 filename);
 
#ifndef WIN32
    if (chmod(filename, mode))
        pg_fatal("could not set permissions on directory \"%s\": %m",
                 filename);
#endif
}

References filename, mkdir, mode, pg_dir_create_mode, pg_fatal, and should_allow_existing_directory().

Referenced by astreamer_extractor_content().

extract_link()

static void extract_link ( const char *  filename, const char *  linktarget  )

static

Definition at line 346 of file astreamer_file.c.

{
    if (symlink(linktarget, filename) != 0)
        pg_fatal("could not create symbolic link from \"%s\" to \"%s\": %m",
                 filename, linktarget);
}

References filename, pg_fatal, and symlink.

Referenced by astreamer_extractor_content().

should_allow_existing_directory()

static bool should_allow_existing_directory ( const char *  pathname )

static

Definition at line 296 of file astreamer_file.c.

{
    const char *filename = last_dir_separator(pathname) + 1;
 
    if (strcmp(filename, "pg_wal") == 0 ||
        strcmp(filename, "pg_xlog") == 0 ||
        strcmp(filename, "archive_status") == 0 ||
        strcmp(filename, "summaries") == 0 ||
        strcmp(filename, "pg_tblspc") == 0)
        return true;
 
    if (strspn(filename, "0123456789") == strlen(filename))
    {
        const char *pg_tblspc = strstr(pathname, "/pg_tblspc/");
 
        return pg_tblspc != NULL && pg_tblspc + 11 == filename;
    }
 
    return false;
}

References filename, and last_dir_separator().

Referenced by extract_directory().

Variable Documentation

astreamer_extractor_ops

const astreamer_ops astreamer_extractor_ops

static

Initial value:

= {
    .content = astreamer_extractor_content,
    .finalize = astreamer_extractor_finalize,
    .free = astreamer_extractor_free
}

Definition at line 66 of file astreamer_file.c.

Referenced by astreamer_extractor_new().

astreamer_plain_writer_ops

const astreamer_ops astreamer_plain_writer_ops

static

Initial value:

= {
    .content = astreamer_plain_writer_content,
    .finalize = astreamer_plain_writer_finalize,
    .free = astreamer_plain_writer_free
}

Definition at line 50 of file astreamer_file.c.

Referenced by astreamer_plain_writer_new().