postgresql/contrib/adminpack/adminpack.c
Tom Lane 7feedda098 Marginal code cleanups in pg_logdir_ls: use ReadDir not readdir,
and avoid scribbling on its result (might be safe but why risk it)
2006-10-20 00:59:03 +00:00

396 lines
8.3 KiB
C

/*-------------------------------------------------------------------------
*
* adminpack.c
*
*
* Copyright (c) 2002 - 2006, PostgreSQL Global Development Group
*
* Author: Andreas Pflug <pgadmin@pse-consulting.de>
*
* IDENTIFICATION
* $PostgreSQL: pgsql/contrib/adminpack/adminpack.c,v 1.7 2006/10/20 00:59:03 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <sys/file.h>
#include <sys/stat.h>
#include <unistd.h>
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "postmaster/syslogger.h"
#include "storage/fd.h"
#include "utils/datetime.h"
#ifdef WIN32
#ifdef rename
#undef rename
#endif
#ifdef unlink
#undef unlink
#endif
#endif
PG_MODULE_MAGIC;
Datum pg_file_write(PG_FUNCTION_ARGS);
Datum pg_file_rename(PG_FUNCTION_ARGS);
Datum pg_file_unlink(PG_FUNCTION_ARGS);
Datum pg_logdir_ls(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(pg_file_write);
PG_FUNCTION_INFO_V1(pg_file_rename);
PG_FUNCTION_INFO_V1(pg_file_unlink);
PG_FUNCTION_INFO_V1(pg_logdir_ls);
typedef struct
{
char *location;
DIR *dirdesc;
} directory_fctx;
/*-----------------------
* some helper functions
*/
/*
* Return an absolute path. Argument may be absolute or
* relative to the DataDir.
*/
static char *
absClusterPath(text *arg, bool logAllowed)
{
char *filename;
int len = VARSIZE(arg) - VARHDRSZ;
int dlen = strlen(DataDir);
filename = palloc(len + 1);
memcpy(filename, VARDATA(arg), len);
filename[len] = 0;
if (strstr(filename, "..") != NULL)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("No .. allowed in filenames"))));
if (is_absolute_path(filename))
{
if (logAllowed && !strncmp(filename, Log_directory, strlen(Log_directory)))
return filename;
if (strncmp(filename, DataDir, dlen))
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("Absolute path not allowed"))));
return filename;
}
else
{
char *absname = palloc(dlen + len + 2);
sprintf(absname, "%s/%s", DataDir, filename);
pfree(filename);
return absname;
}
}
/*
* check for superuser, bark if not.
*/
static void
requireSuperuser(void)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("only superuser may access generic file functions"))));
}
/* ------------------------------------
* generic file handling functions
*/
Datum
pg_file_write(PG_FUNCTION_ARGS)
{
FILE *f;
char *filename;
text *data;
int64 count = 0;
requireSuperuser();
filename = absClusterPath(PG_GETARG_TEXT_P(0), false);
data = PG_GETARG_TEXT_P(1);
if (PG_ARGISNULL(2) || !PG_GETARG_BOOL(2))
{
struct stat fst;
if (stat(filename, &fst) >= 0)
ereport(ERROR,
(ERRCODE_DUPLICATE_FILE,
errmsg("file %s exists", filename)));
f = fopen(filename, "wb");
}
else
f = fopen(filename, "ab");
if (!f)
{
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could open file %s for writing: %m", filename)));
}
if (VARSIZE(data) != 0)
{
count = fwrite(VARDATA(data), 1, VARSIZE(data) - VARHDRSZ, f);
if (count != VARSIZE(data) - VARHDRSZ)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("error writing file %s: %m", filename)));
}
fclose(f);
PG_RETURN_INT64(count);
}
Datum
pg_file_rename(PG_FUNCTION_ARGS)
{
char *fn1,
*fn2,
*fn3;
int rc;
requireSuperuser();
if (PG_ARGISNULL(0) || PG_ARGISNULL(1))
PG_RETURN_NULL();
fn1 = absClusterPath(PG_GETARG_TEXT_P(0), false);
fn2 = absClusterPath(PG_GETARG_TEXT_P(1), false);
if (PG_ARGISNULL(2))
fn3 = 0;
else
fn3 = absClusterPath(PG_GETARG_TEXT_P(2), false);
if (access(fn1, W_OK) < 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("file %s not accessible: %m", fn1)));
PG_RETURN_BOOL(false);
}
if (fn3 && access(fn2, W_OK) < 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("file %s not accessible: %m", fn2)));
PG_RETURN_BOOL(false);
}
rc = access(fn3 ? fn3 : fn2, 2);
if (rc >= 0 || errno != ENOENT)
{
ereport(ERROR,
(ERRCODE_DUPLICATE_FILE,
errmsg("cannot rename to target file %s", fn3 ? fn3 : fn2)));
}
if (fn3)
{
if (rename(fn2, fn3) != 0)
{
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not rename %s to %s: %m", fn2, fn3)));
}
if (rename(fn1, fn2) != 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("could not rename %s to %s: %m", fn1, fn2)));
if (rename(fn3, fn2) != 0)
{
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not rename %s back to %s: %m", fn3, fn2)));
}
else
{
ereport(ERROR,
(ERRCODE_UNDEFINED_FILE,
errmsg("renaming %s to %s was reverted", fn2, fn3)));
}
}
}
else if (rename(fn1, fn2) != 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("renaming %s to %s %m", fn1, fn2)));
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not rename %s to %s: %m", fn1, fn2)));
}
PG_RETURN_BOOL(true);
}
Datum
pg_file_unlink(PG_FUNCTION_ARGS)
{
char *filename;
requireSuperuser();
filename = absClusterPath(PG_GETARG_TEXT_P(0), false);
if (access(filename, W_OK) < 0)
{
if (errno == ENOENT)
PG_RETURN_BOOL(false);
else
ereport(ERROR,
(errcode_for_file_access(),
errmsg("file %s not accessible: %m", filename)));
}
if (unlink(filename) < 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("could not unlink file %s: %m", filename)));
PG_RETURN_BOOL(false);
}
PG_RETURN_BOOL(true);
}
Datum
pg_logdir_ls(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
struct dirent *de;
directory_fctx *fctx;
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("only superuser can list the log directory"))));
if (strcmp(Log_filename, "postgresql-%Y-%m-%d_%H%M%S.log") != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
(errmsg("the log_filename parameter must equal 'postgresql-%%Y-%%m-%%d_%%H%%M%%S.log'"))));
if (SRF_IS_FIRSTCALL())
{
MemoryContext oldcontext;
TupleDesc tupdesc;
funcctx = SRF_FIRSTCALL_INIT();
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
fctx = palloc(sizeof(directory_fctx));
if (is_absolute_path(Log_directory))
fctx->location = pstrdup(Log_directory);
else
{
fctx->location = palloc(strlen(DataDir) + strlen(Log_directory) + 2);
sprintf(fctx->location, "%s/%s", DataDir, Log_directory);
}
tupdesc = CreateTemplateTupleDesc(2, false);
TupleDescInitEntry(tupdesc, (AttrNumber) 1, "starttime",
TIMESTAMPOID, -1, 0);
TupleDescInitEntry(tupdesc, (AttrNumber) 2, "filename",
TEXTOID, -1, 0);
funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
fctx->dirdesc = AllocateDir(fctx->location);
if (!fctx->dirdesc)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("%s is not browsable: %m", fctx->location)));
funcctx->user_fctx = fctx;
MemoryContextSwitchTo(oldcontext);
}
funcctx = SRF_PERCALL_SETUP();
fctx = (directory_fctx *) funcctx->user_fctx;
while ((de = ReadDir(fctx->dirdesc, fctx->location)) != NULL)
{
char *values[2];
HeapTuple tuple;
char timestampbuf[32];
char *field[MAXDATEFIELDS];
char lowstr[MAXDATELEN + 1];
int dtype;
int nf,
ftype[MAXDATEFIELDS];
fsec_t fsec;
int tz = 0;
struct pg_tm date;
/*
* Default format: postgresql-YYYY-MM-DD_HHMMSS.log
*/
if (strlen(de->d_name) != 32
|| strncmp(de->d_name, "postgresql-", 11) != 0
|| de->d_name[21] != '_'
|| strcmp(de->d_name + 28, ".log") != 0)
continue;
/* extract timestamp portion of filename */
strcpy(timestampbuf, de->d_name + 11);
timestampbuf[17] = '\0';
/* parse and decode expected timestamp to verify it's OK format */
if (ParseDateTime(timestampbuf, lowstr, MAXDATELEN, field, ftype, MAXDATEFIELDS, &nf))
continue;
if (DecodeDateTime(field, ftype, nf, &dtype, &date, &fsec, &tz))
continue;
/* Seems the timestamp is OK; prepare and return tuple */
values[0] = timestampbuf;
values[1] = palloc(strlen(fctx->location) + strlen(de->d_name) + 2);
sprintf(values[1], "%s/%s", fctx->location, de->d_name);
tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple));
}
FreeDir(fctx->dirdesc);
SRF_RETURN_DONE(funcctx);
}