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postgresql/src/bin/pg_dump/dumputils.c

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/*-------------------------------------------------------------------------
*
* Utility routines for SQL dumping
* Basically this is stuff that is useful in both pg_dump and pg_dumpall.
* Lately it's also being used by psql and bin/scripts/ ...
*
*
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/bin/pg_dump/dumputils.c,v 1.54 2010/02/18 01:29:10 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <ctype.h>
#include "dumputils.h"
#include "parser/keywords.h"
#define supports_grant_options(version) ((version) >= 70400)
static bool parseAclItem(const char *item, const char *type,
const char *name, const char *subname, int remoteVersion,
PQExpBuffer grantee, PQExpBuffer grantor,
PQExpBuffer privs, PQExpBuffer privswgo);
static char *copyAclUserName(PQExpBuffer output, char *input);
static void AddAcl(PQExpBuffer aclbuf, const char *keyword,
const char *subname);
#ifdef WIN32
static bool parallel_init_done = false;
static DWORD tls_index;
#endif
void
init_parallel_dump_utils(void)
{
#ifdef WIN32
if (!parallel_init_done)
{
tls_index = TlsAlloc();
parallel_init_done = true;
}
#endif
}
/*
* Quotes input string if it's not a legitimate SQL identifier as-is.
*
* Note that the returned string must be used before calling fmtId again,
* since we re-use the same return buffer each time. Non-reentrant but
* reduces memory leakage. (On Windows the memory leakage will be one buffer
* per thread, which is at least better than one per call).
*/
const char *
fmtId(const char *rawid)
{
/*
* The Tls code goes awry if we use a static var, so we provide for both
* static and auto, and omit any use of the static var when using Tls.
*/
static PQExpBuffer s_id_return = NULL;
PQExpBuffer id_return;
const char *cp;
bool need_quotes = false;
#ifdef WIN32
if (parallel_init_done)
id_return = (PQExpBuffer) TlsGetValue(tls_index); /* 0 when not set */
else
id_return = s_id_return;
#else
id_return = s_id_return;
#endif
if (id_return) /* first time through? */
{
/* same buffer, just wipe contents */
resetPQExpBuffer(id_return);
}
else
{
/* new buffer */
id_return = createPQExpBuffer();
#ifdef WIN32
if (parallel_init_done)
TlsSetValue(tls_index, id_return);
else
s_id_return = id_return;
#else
s_id_return = id_return;
#endif
}
/*
* These checks need to match the identifier production in scan.l. Don't
* use islower() etc.
*/
/* slightly different rules for first character */
if (!((rawid[0] >= 'a' && rawid[0] <= 'z') || rawid[0] == '_'))
need_quotes = true;
else
{
/* otherwise check the entire string */
for (cp = rawid; *cp; cp++)
{
if (!((*cp >= 'a' && *cp <= 'z')
|| (*cp >= '0' && *cp <= '9')
|| (*cp == '_')))
{
need_quotes = true;
break;
}
}
}
if (!need_quotes)
{
/*
* Check for keyword. We quote keywords except for unreserved ones.
* (In some cases we could avoid quoting a col_name or type_func_name
* keyword, but it seems much harder than it's worth to tell that.)
*
* Note: ScanKeywordLookup() does case-insensitive comparison, but
* that's fine, since we already know we have all-lower-case.
*/
const ScanKeyword *keyword = ScanKeywordLookup(rawid,
ScanKeywords,
NumScanKeywords);
if (keyword != NULL && keyword->category != UNRESERVED_KEYWORD)
need_quotes = true;
}
if (!need_quotes)
{
/* no quoting needed */
appendPQExpBufferStr(id_return, rawid);
}
else
{
appendPQExpBufferChar(id_return, '\"');
for (cp = rawid; *cp; cp++)
{
/*
* Did we find a double-quote in the string? Then make this a
* double double-quote per SQL99. Before, we put in a
* backslash/double-quote pair. - thomas 2000-08-05
*/
if (*cp == '\"')
appendPQExpBufferChar(id_return, '\"');
appendPQExpBufferChar(id_return, *cp);
}
appendPQExpBufferChar(id_return, '\"');
}
return id_return->data;
}
/*
* Convert a string value to an SQL string literal and append it to
* the given buffer. We assume the specified client_encoding and
* standard_conforming_strings settings.
*
* This is essentially equivalent to libpq's PQescapeStringInternal,
* except for the output buffer structure. We need it in situations
* where we do not have a PGconn available. Where we do,
* appendStringLiteralConn is a better choice.
*/
void
appendStringLiteral(PQExpBuffer buf, const char *str,
int encoding, bool std_strings)
{
size_t length = strlen(str);
const char *source = str;
char *target;
if (!enlargePQExpBuffer(buf, 2 * length + 2))
return;
target = buf->data + buf->len;
*target++ = '\'';
while (*source != '\0')
{
char c = *source;
int len;
int i;
/* Fast path for plain ASCII */
if (!IS_HIGHBIT_SET(c))
{
/* Apply quoting if needed */
if (SQL_STR_DOUBLE(c, !std_strings))
*target++ = c;
/* Copy the character */
*target++ = c;
source++;
continue;
}
/* Slow path for possible multibyte characters */
len = PQmblen(source, encoding);
/* Copy the character */
for (i = 0; i < len; i++)
{
if (*source == '\0')
break;
*target++ = *source++;
}
/*
* If we hit premature end of string (ie, incomplete multibyte
* character), try to pad out to the correct length with spaces. We
* may not be able to pad completely, but we will always be able to
* insert at least one pad space (since we'd not have quoted a
* multibyte character). This should be enough to make a string that
* the server will error out on.
*/
if (i < len)
{
char *stop = buf->data + buf->maxlen - 2;
for (; i < len; i++)
{
if (target >= stop)
break;
*target++ = ' ';
}
break;
}
}
/* Write the terminating quote and NUL character. */
*target++ = '\'';
*target = '\0';
buf->len = target - buf->data;
}
/*
* Convert a string value to an SQL string literal and append it to
* the given buffer. Encoding and string syntax rules are as indicated
* by current settings of the PGconn.
*/
void
appendStringLiteralConn(PQExpBuffer buf, const char *str, PGconn *conn)
{
size_t length = strlen(str);
/*
* XXX This is a kluge to silence escape_string_warning in our utility
* programs. It should go away someday.
*/
if (strchr(str, '\\') != NULL && PQserverVersion(conn) >= 80100)
{
/* ensure we are not adjacent to an identifier */
if (buf->len > 0 && buf->data[buf->len - 1] != ' ')
appendPQExpBufferChar(buf, ' ');
appendPQExpBufferChar(buf, ESCAPE_STRING_SYNTAX);
appendStringLiteral(buf, str, PQclientEncoding(conn), false);
return;
}
/* XXX end kluge */
if (!enlargePQExpBuffer(buf, 2 * length + 2))
return;
appendPQExpBufferChar(buf, '\'');
buf->len += PQescapeStringConn(conn, buf->data + buf->len,
str, length, NULL);
appendPQExpBufferChar(buf, '\'');
}
/*
* Convert a string value to a dollar quoted literal and append it to
* the given buffer. If the dqprefix parameter is not NULL then the
* dollar quote delimiter will begin with that (after the opening $).
*
* No escaping is done at all on str, in compliance with the rules
* for parsing dollar quoted strings. Also, we need not worry about
* encoding issues.
*/
void
appendStringLiteralDQ(PQExpBuffer buf, const char *str, const char *dqprefix)
{
static const char suffixes[] = "_XXXXXXX";
int nextchar = 0;
PQExpBuffer delimBuf = createPQExpBuffer();
/* start with $ + dqprefix if not NULL */
appendPQExpBufferChar(delimBuf, '$');
if (dqprefix)
appendPQExpBufferStr(delimBuf, dqprefix);
/*
* Make sure we choose a delimiter which (without the trailing $) is not
* present in the string being quoted. We don't check with the trailing $
* because a string ending in $foo must not be quoted with $foo$.
*/
while (strstr(str, delimBuf->data) != NULL)
{
appendPQExpBufferChar(delimBuf, suffixes[nextchar++]);
nextchar %= sizeof(suffixes) - 1;
}
/* add trailing $ */
appendPQExpBufferChar(delimBuf, '$');
/* quote it and we are all done */
appendPQExpBufferStr(buf, delimBuf->data);
appendPQExpBufferStr(buf, str);
appendPQExpBufferStr(buf, delimBuf->data);
destroyPQExpBuffer(delimBuf);
}
/*
* Convert a bytea value (presented as raw bytes) to an SQL string literal
* and append it to the given buffer. We assume the specified
* standard_conforming_strings setting.
*
* This is needed in situations where we do not have a PGconn available.
* Where we do, PQescapeByteaConn is a better choice.
*/
void
appendByteaLiteral(PQExpBuffer buf, const unsigned char *str, size_t length,
bool std_strings)
{
const unsigned char *source = str;
char *target;
static const char hextbl[] = "0123456789abcdef";
/*
* This implementation is hard-wired to produce hex-format output.
* We do not know the server version the output will be loaded into,
* so making an intelligent format choice is impossible. It might be
* better to always use the old escaped format.
*/
if (!enlargePQExpBuffer(buf, 2 * length + 5))
return;
target = buf->data + buf->len;
*target++ = '\'';
if (!std_strings)
*target++ = '\\';
*target++ = '\\';
*target++ = 'x';
while (length-- > 0)
{
unsigned char c = *source++;
*target++ = hextbl[(c >> 4) & 0xF];
*target++ = hextbl[c & 0xF];
}
/* Write the terminating quote and NUL character. */
*target++ = '\'';
*target = '\0';
buf->len = target - buf->data;
}
/*
* Convert backend's version string into a number.
*/
int
parse_version(const char *versionString)
{
int cnt;
int vmaj,
vmin,
vrev;
cnt = sscanf(versionString, "%d.%d.%d", &vmaj, &vmin, &vrev);
if (cnt < 2)
return -1;
if (cnt == 2)
vrev = 0;
return (100 * vmaj + vmin) * 100 + vrev;
}
/*
* Deconstruct the text representation of a 1-dimensional Postgres array
* into individual items.
*
* On success, returns true and sets *itemarray and *nitems to describe
* an array of individual strings. On parse failure, returns false;
* *itemarray may exist or be NULL.
*
* NOTE: free'ing itemarray is sufficient to deallocate the working storage.
*/
bool
parsePGArray(const char *atext, char ***itemarray, int *nitems)
{
int inputlen;
char **items;
char *strings;
int curitem;
/*
* We expect input in the form of "{item,item,item}" where any item is
* either raw data, or surrounded by double quotes (in which case embedded
* characters including backslashes and quotes are backslashed).
*
* We build the result as an array of pointers followed by the actual
* string data, all in one malloc block for convenience of deallocation.
* The worst-case storage need is not more than one pointer and one
* character for each input character (consider "{,,,,,,,,,,}").
*/
*itemarray = NULL;
*nitems = 0;
inputlen = strlen(atext);
if (inputlen < 2 || atext[0] != '{' || atext[inputlen - 1] != '}')
return false; /* bad input */
items = (char **) malloc(inputlen * (sizeof(char *) + sizeof(char)));
if (items == NULL)
return false; /* out of memory */
*itemarray = items;
strings = (char *) (items + inputlen);
atext++; /* advance over initial '{' */
curitem = 0;
while (*atext != '}')
{
if (*atext == '\0')
return false; /* premature end of string */
items[curitem] = strings;
while (*atext != '}' && *atext != ',')
{
if (*atext == '\0')
return false; /* premature end of string */
if (*atext != '"')
*strings++ = *atext++; /* copy unquoted data */
else
{
/* process quoted substring */
atext++;
while (*atext != '"')
{
if (*atext == '\0')
return false; /* premature end of string */
if (*atext == '\\')
{
atext++;
if (*atext == '\0')
return false; /* premature end of string */
}
*strings++ = *atext++; /* copy quoted data */
}
atext++;
}
}
*strings++ = '\0';
if (*atext == ',')
atext++;
curitem++;
}
if (atext[1] != '\0')
return false; /* bogus syntax (embedded '}') */
*nitems = curitem;
return true;
}
/*
* Build GRANT/REVOKE command(s) for an object.
*
* name: the object name, in the form to use in the commands (already quoted)
* subname: the sub-object name, if any (already quoted); NULL if none
* type: the object type (as seen in GRANT command: must be one of
* TABLE, SEQUENCE, FUNCTION, LANGUAGE, SCHEMA, DATABASE, TABLESPACE,
* FOREIGN DATA WRAPPER, SERVER, or LARGE OBJECT)
* acls: the ACL string fetched from the database
* owner: username of object owner (will be passed through fmtId); can be
* NULL or empty string to indicate "no owner known"
* prefix: string to prefix to each generated command; typically empty
* remoteVersion: version of database
*
* Returns TRUE if okay, FALSE if could not parse the acl string.
* The resulting commands (if any) are appended to the contents of 'sql'.
*
* Note: when processing a default ACL, prefix is "ALTER DEFAULT PRIVILEGES "
* or something similar, and name is an empty string.
*
* Note: beware of passing a fmtId() result directly as 'name' or 'subname',
* since this routine uses fmtId() internally.
*/
bool
buildACLCommands(const char *name, const char *subname,
const char *type, const char *acls, const char *owner,
const char *prefix, int remoteVersion,
PQExpBuffer sql)
{
char **aclitems;
int naclitems;
int i;
PQExpBuffer grantee,
grantor,
privs,
privswgo;
PQExpBuffer firstsql,
secondsql;
bool found_owner_privs = false;
if (strlen(acls) == 0)
return true; /* object has default permissions */
/* treat empty-string owner same as NULL */
if (owner && *owner == '\0')
owner = NULL;
if (!parsePGArray(acls, &aclitems, &naclitems))
{
if (aclitems)
free(aclitems);
return false;
}
grantee = createPQExpBuffer();
grantor = createPQExpBuffer();
privs = createPQExpBuffer();
privswgo = createPQExpBuffer();
/*
* At the end, these two will be pasted together to form the result. But
* the owner privileges need to go before the other ones to keep the
* dependencies valid. In recent versions this is normally the case, but
* in old versions they come after the PUBLIC privileges and that results
* in problems if we need to run REVOKE on the owner privileges.
*/
firstsql = createPQExpBuffer();
secondsql = createPQExpBuffer();
/*
* Always start with REVOKE ALL FROM PUBLIC, so that we don't have to
* wire-in knowledge about the default public privileges for different
* kinds of objects.
*/
appendPQExpBuffer(firstsql, "%sREVOKE ALL", prefix);
if (subname)
appendPQExpBuffer(firstsql, "(%s)", subname);
appendPQExpBuffer(firstsql, " ON %s %s FROM PUBLIC;\n", type, name);
/*
* We still need some hacking though to cover the case where new default
* public privileges are added in new versions: the REVOKE ALL will revoke
* them, leading to behavior different from what the old version had,
* which is generally not what's wanted. So add back default privs if the
* source database is too old to have had that particular priv.
*/
if (remoteVersion < 80200 && strcmp(type, "DATABASE") == 0)
{
/* database CONNECT priv didn't exist before 8.2 */
appendPQExpBuffer(firstsql, "%sGRANT CONNECT ON %s %s TO PUBLIC;\n",
prefix, type, name);
}
/* Scan individual ACL items */
for (i = 0; i < naclitems; i++)
{
if (!parseAclItem(aclitems[i], type, name, subname, remoteVersion,
grantee, grantor, privs, privswgo))
return false;
if (grantor->len == 0 && owner)
printfPQExpBuffer(grantor, "%s", owner);
if (privs->len > 0 || privswgo->len > 0)
{
if (owner
&& strcmp(grantee->data, owner) == 0
&& strcmp(grantor->data, owner) == 0)
{
found_owner_privs = true;
/*
* For the owner, the default privilege level is ALL WITH
* GRANT OPTION (only ALL prior to 7.4).
*/
if (supports_grant_options(remoteVersion)
? strcmp(privswgo->data, "ALL") != 0
: strcmp(privs->data, "ALL") != 0)
{
appendPQExpBuffer(firstsql, "%sREVOKE ALL", prefix);
if (subname)
appendPQExpBuffer(firstsql, "(%s)", subname);
appendPQExpBuffer(firstsql, " ON %s %s FROM %s;\n",
type, name, fmtId(grantee->data));
if (privs->len > 0)
appendPQExpBuffer(firstsql,
"%sGRANT %s ON %s %s TO %s;\n",
prefix, privs->data, type, name,
fmtId(grantee->data));
if (privswgo->len > 0)
appendPQExpBuffer(firstsql,
"%sGRANT %s ON %s %s TO %s WITH GRANT OPTION;\n",
prefix, privswgo->data, type, name,
fmtId(grantee->data));
}
}
else
{
/*
* Otherwise can assume we are starting from no privs.
*/
if (grantor->len > 0
&& (!owner || strcmp(owner, grantor->data) != 0))
appendPQExpBuffer(secondsql, "SET SESSION AUTHORIZATION %s;\n",
fmtId(grantor->data));
if (privs->len > 0)
{
appendPQExpBuffer(secondsql, "%sGRANT %s ON %s %s TO ",
prefix, privs->data, type, name);
if (grantee->len == 0)
appendPQExpBuffer(secondsql, "PUBLIC;\n");
else if (strncmp(grantee->data, "group ",
strlen("group ")) == 0)
appendPQExpBuffer(secondsql, "GROUP %s;\n",
fmtId(grantee->data + strlen("group ")));
else
appendPQExpBuffer(secondsql, "%s;\n", fmtId(grantee->data));
}
if (privswgo->len > 0)
{
appendPQExpBuffer(secondsql, "%sGRANT %s ON %s %s TO ",
prefix, privswgo->data, type, name);
if (grantee->len == 0)
appendPQExpBuffer(secondsql, "PUBLIC");
else if (strncmp(grantee->data, "group ",
strlen("group ")) == 0)
appendPQExpBuffer(secondsql, "GROUP %s",
fmtId(grantee->data + strlen("group ")));
else
appendPQExpBuffer(secondsql, "%s", fmtId(grantee->data));
appendPQExpBuffer(secondsql, " WITH GRANT OPTION;\n");
}
if (grantor->len > 0
&& (!owner || strcmp(owner, grantor->data) != 0))
appendPQExpBuffer(secondsql, "RESET SESSION AUTHORIZATION;\n");
}
}
}
/*
* If we didn't find any owner privs, the owner must have revoked 'em all
*/
if (!found_owner_privs && owner)
{
appendPQExpBuffer(firstsql, "%sREVOKE ALL", prefix);
if (subname)
appendPQExpBuffer(firstsql, "(%s)", subname);
appendPQExpBuffer(firstsql, " ON %s %s FROM %s;\n",
type, name, fmtId(owner));
}
destroyPQExpBuffer(grantee);
destroyPQExpBuffer(grantor);
destroyPQExpBuffer(privs);
destroyPQExpBuffer(privswgo);
appendPQExpBuffer(sql, "%s%s", firstsql->data, secondsql->data);
destroyPQExpBuffer(firstsql);
destroyPQExpBuffer(secondsql);
free(aclitems);
return true;
}
/*
* Build ALTER DEFAULT PRIVILEGES command(s) for single pg_default_acl entry.
*
* type: the object type (TABLES, FUNCTIONS, etc)
* nspname: schema name, or NULL for global default privileges
* acls: the ACL string fetched from the database
* owner: username of privileges owner (will be passed through fmtId)
* remoteVersion: version of database
*
* Returns TRUE if okay, FALSE if could not parse the acl string.
* The resulting commands (if any) are appended to the contents of 'sql'.
*/
bool
buildDefaultACLCommands(const char *type, const char *nspname,
const char *acls, const char *owner,
int remoteVersion,
PQExpBuffer sql)
{
bool result;
PQExpBuffer prefix;
prefix = createPQExpBuffer();
/*
* We incorporate the target role directly into the command, rather than
* playing around with SET ROLE or anything like that. This is so that
* a permissions error leads to nothing happening, rather than
* changing default privileges for the wrong user.
*/
appendPQExpBuffer(prefix, "ALTER DEFAULT PRIVILEGES FOR ROLE %s ",
fmtId(owner));
if (nspname)
appendPQExpBuffer(prefix, "IN SCHEMA %s ", fmtId(nspname));
result = buildACLCommands("", NULL,
type, acls, owner,
prefix->data, remoteVersion,
sql);
destroyPQExpBuffer(prefix);
return result;
}
/*
* This will parse an aclitem string, having the general form
* username=privilegecodes/grantor
* or
* group groupname=privilegecodes/grantor
* (the /grantor part will not be present if pre-7.4 database).
*
* The returned grantee string will be the dequoted username or groupname
* (preceded with "group " in the latter case). The returned grantor is
* the dequoted grantor name or empty. Privilege characters are decoded
* and split between privileges with grant option (privswgo) and without
* (privs).
*
* Note: for cross-version compatibility, it's important to use ALL when
* appropriate.
*/
static bool
parseAclItem(const char *item, const char *type,
const char *name, const char *subname, int remoteVersion,
PQExpBuffer grantee, PQExpBuffer grantor,
PQExpBuffer privs, PQExpBuffer privswgo)
{
char *buf;
bool all_with_go = true;
bool all_without_go = true;
char *eqpos;
char *slpos;
char *pos;
buf = strdup(item);
if (!buf)
return false;
/* user or group name is string up to = */
eqpos = copyAclUserName(grantee, buf);
if (*eqpos != '=')
return false;
/* grantor may be listed after / */
slpos = strchr(eqpos + 1, '/');
if (slpos)
{
*slpos++ = '\0';
slpos = copyAclUserName(grantor, slpos);
if (*slpos != '\0')
return false;
}
else
resetPQExpBuffer(grantor);
/* privilege codes */
#define CONVERT_PRIV(code, keywd) \
do { \
if ((pos = strchr(eqpos + 1, code))) \
{ \
if (*(pos + 1) == '*') \
{ \
AddAcl(privswgo, keywd, subname); \
all_without_go = false; \
} \
else \
{ \
AddAcl(privs, keywd, subname); \
all_with_go = false; \
} \
} \
else \
all_with_go = all_without_go = false; \
} while (0)
resetPQExpBuffer(privs);
resetPQExpBuffer(privswgo);
if (strcmp(type, "TABLE") == 0 || strcmp(type, "SEQUENCE") == 0 ||
strcmp(type, "TABLES") == 0 || strcmp(type, "SEQUENCES") == 0)
{
CONVERT_PRIV('r', "SELECT");
if (strcmp(type, "SEQUENCE") == 0 ||
strcmp(type, "SEQUENCES") == 0)
/* sequence only */
CONVERT_PRIV('U', "USAGE");
else
{
/* table only */
CONVERT_PRIV('a', "INSERT");
if (remoteVersion >= 70200)
CONVERT_PRIV('x', "REFERENCES");
/* rest are not applicable to columns */
if (subname == NULL)
{
if (remoteVersion >= 70200)
{
CONVERT_PRIV('d', "DELETE");
CONVERT_PRIV('t', "TRIGGER");
}
if (remoteVersion >= 80400)
CONVERT_PRIV('D', "TRUNCATE");
}
}
/* UPDATE */
if (remoteVersion >= 70200 ||
strcmp(type, "SEQUENCE") == 0 ||
strcmp(type, "SEQUENCES") == 0)
CONVERT_PRIV('w', "UPDATE");
else
/* 7.0 and 7.1 have a simpler worldview */
CONVERT_PRIV('w', "UPDATE,DELETE");
}
else if (strcmp(type, "FUNCTION") == 0 ||
strcmp(type, "FUNCTIONS") == 0)
CONVERT_PRIV('X', "EXECUTE");
else if (strcmp(type, "LANGUAGE") == 0)
CONVERT_PRIV('U', "USAGE");
else if (strcmp(type, "SCHEMA") == 0)
{
CONVERT_PRIV('C', "CREATE");
CONVERT_PRIV('U', "USAGE");
}
else if (strcmp(type, "DATABASE") == 0)
{
CONVERT_PRIV('C', "CREATE");
CONVERT_PRIV('c', "CONNECT");
CONVERT_PRIV('T', "TEMPORARY");
}
else if (strcmp(type, "TABLESPACE") == 0)
CONVERT_PRIV('C', "CREATE");
else if (strcmp(type, "FOREIGN DATA WRAPPER") == 0)
CONVERT_PRIV('U', "USAGE");
else if (strcmp(type, "SERVER") == 0)
CONVERT_PRIV('U', "USAGE");
else if (strcmp(type, "LARGE OBJECT") == 0)
{
CONVERT_PRIV('r', "SELECT");
CONVERT_PRIV('w', "UPDATE");
}
else
abort();
#undef CONVERT_PRIV
if (all_with_go)
{
resetPQExpBuffer(privs);
printfPQExpBuffer(privswgo, "ALL");
if (subname)
appendPQExpBuffer(privswgo, "(%s)", subname);
}
else if (all_without_go)
{
resetPQExpBuffer(privswgo);
printfPQExpBuffer(privs, "ALL");
if (subname)
appendPQExpBuffer(privs, "(%s)", subname);
}
free(buf);
return true;
}
/*
* Transfer a user or group name starting at *input into the output buffer,
* dequoting if needed. Returns a pointer to just past the input name.
* The name is taken to end at an unquoted '=' or end of string.
*/
static char *
copyAclUserName(PQExpBuffer output, char *input)
{
resetPQExpBuffer(output);
while (*input && *input != '=')
{
/*
* If user name isn't quoted, then just add it to the output buffer
*/
if (*input != '"')
appendPQExpBufferChar(output, *input++);
else
{
/* Otherwise, it's a quoted username */
input++;
/* Loop until we come across an unescaped quote */
while (!(*input == '"' && *(input + 1) != '"'))
{
if (*input == '\0')
return input; /* really a syntax error... */
/*
* Quoting convention is to escape " as "". Keep this code in
* sync with putid() in backend's acl.c.
*/
if (*input == '"' && *(input + 1) == '"')
input++;
appendPQExpBufferChar(output, *input++);
}
input++;
}
}
return input;
}
/*
* Append a privilege keyword to a keyword list, inserting comma if needed.
*/
static void
AddAcl(PQExpBuffer aclbuf, const char *keyword, const char *subname)
{
if (aclbuf->len > 0)
appendPQExpBufferChar(aclbuf, ',');
appendPQExpBuffer(aclbuf, "%s", keyword);
if (subname)
appendPQExpBuffer(aclbuf, "(%s)", subname);
}
/*
* processSQLNamePattern
*
* Scan a wildcard-pattern string and generate appropriate WHERE clauses
* to limit the set of objects returned. The WHERE clauses are appended
* to the already-partially-constructed query in buf. Returns whether
* any clause was added.
*
* conn: connection query will be sent to (consulted for escaping rules).
* buf: output parameter.
* pattern: user-specified pattern option, or NULL if none ("*" is implied).
* have_where: true if caller already emitted "WHERE" (clauses will be ANDed
* onto the existing WHERE clause).
* force_escape: always quote regexp special characters, even outside
* double quotes (else they are quoted only between double quotes).
* schemavar: name of query variable to match against a schema-name pattern.
* Can be NULL if no schema.
* namevar: name of query variable to match against an object-name pattern.
* altnamevar: NULL, or name of an alternative variable to match against name.
* visibilityrule: clause to use if we want to restrict to visible objects
* (for example, "pg_catalog.pg_table_is_visible(p.oid)"). Can be NULL.
*
* Formatting note: the text already present in buf should end with a newline.
* The appended text, if any, will end with one too.
*/
bool
processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
bool have_where, bool force_escape,
const char *schemavar, const char *namevar,
const char *altnamevar, const char *visibilityrule)
{
PQExpBufferData schemabuf;
PQExpBufferData namebuf;
int encoding = PQclientEncoding(conn);
bool inquotes;
const char *cp;
int i;
bool added_clause = false;
#define WHEREAND() \
(appendPQExpBufferStr(buf, have_where ? " AND " : "WHERE "), \
have_where = true, added_clause = true)
if (pattern == NULL)
{
/* Default: select all visible objects */
if (visibilityrule)
{
WHEREAND();
appendPQExpBuffer(buf, "%s\n", visibilityrule);
}
return added_clause;
}
initPQExpBuffer(&schemabuf);
initPQExpBuffer(&namebuf);
/*
* Parse the pattern, converting quotes and lower-casing unquoted letters.
* Also, adjust shell-style wildcard characters into regexp notation.
*
* We surround the pattern with "^(...)$" to force it to match the whole
* string, as per SQL practice. We have to have parens in case the string
* contains "|", else the "^" and "$" will be bound into the first and
* last alternatives which is not what we want.
*
* Note: the result of this pass is the actual regexp pattern(s) we want
* to execute. Quoting/escaping into SQL literal format will be done
* below using appendStringLiteralConn().
*/
appendPQExpBufferStr(&namebuf, "^(");
inquotes = false;
cp = pattern;
while (*cp)
{
char ch = *cp;
if (ch == '"')
{
if (inquotes && cp[1] == '"')
{
/* emit one quote, stay in inquotes mode */
appendPQExpBufferChar(&namebuf, '"');
cp++;
}
else
inquotes = !inquotes;
cp++;
}
else if (!inquotes && isupper((unsigned char) ch))
{
appendPQExpBufferChar(&namebuf,
pg_tolower((unsigned char) ch));
cp++;
}
else if (!inquotes && ch == '*')
{
appendPQExpBufferStr(&namebuf, ".*");
cp++;
}
else if (!inquotes && ch == '?')
{
appendPQExpBufferChar(&namebuf, '.');
cp++;
}
else if (!inquotes && ch == '.')
{
/* Found schema/name separator, move current pattern to schema */
resetPQExpBuffer(&schemabuf);
appendPQExpBufferStr(&schemabuf, namebuf.data);
resetPQExpBuffer(&namebuf);
appendPQExpBufferStr(&namebuf, "^(");
cp++;
}
else if (ch == '$')
{
/*
* Dollar is always quoted, whether inside quotes or not. The
* reason is that it's allowed in SQL identifiers, so there's a
* significant use-case for treating it literally, while because
* we anchor the pattern automatically there is no use-case for
* having it possess its regexp meaning.
*/
appendPQExpBufferStr(&namebuf, "\\$");
cp++;
}
else
{
/*
* Ordinary data character, transfer to pattern
*
* Inside double quotes, or at all times if force_escape is true,
* quote regexp special characters with a backslash to avoid
* regexp errors. Outside quotes, however, let them pass through
* as-is; this lets knowledgeable users build regexp expressions
* that are more powerful than shell-style patterns.
*/
if ((inquotes || force_escape) &&
strchr("|*+?()[]{}.^$\\", ch))
appendPQExpBufferChar(&namebuf, '\\');
i = PQmblen(cp, encoding);
while (i-- && *cp)
{
appendPQExpBufferChar(&namebuf, *cp);
cp++;
}
}
}
/*
* Now decide what we need to emit. Note there will be a leading "^(" in
* the patterns in any case.
*/
if (namebuf.len > 2)
{
/* We have a name pattern, so constrain the namevar(s) */
appendPQExpBufferStr(&namebuf, ")$");
/* Optimize away a "*" pattern */
if (strcmp(namebuf.data, "^(.*)$") != 0)
{
WHEREAND();
if (altnamevar)
{
appendPQExpBuffer(buf, "(%s ~ ", namevar);
appendStringLiteralConn(buf, namebuf.data, conn);
appendPQExpBuffer(buf, "\n OR %s ~ ", altnamevar);
appendStringLiteralConn(buf, namebuf.data, conn);
appendPQExpBufferStr(buf, ")\n");
}
else
{
appendPQExpBuffer(buf, "%s ~ ", namevar);
appendStringLiteralConn(buf, namebuf.data, conn);
appendPQExpBufferChar(buf, '\n');
}
}
}
if (schemabuf.len > 2)
{
/* We have a schema pattern, so constrain the schemavar */
appendPQExpBufferStr(&schemabuf, ")$");
/* Optimize away a "*" pattern */
if (strcmp(schemabuf.data, "^(.*)$") != 0 && schemavar)
{
WHEREAND();
appendPQExpBuffer(buf, "%s ~ ", schemavar);
appendStringLiteralConn(buf, schemabuf.data, conn);
appendPQExpBufferChar(buf, '\n');
}
}
else
{
/* No schema pattern given, so select only visible objects */
if (visibilityrule)
{
WHEREAND();
appendPQExpBuffer(buf, "%s\n", visibilityrule);
}
}
termPQExpBuffer(&schemabuf);
termPQExpBuffer(&namebuf);
return added_clause;
#undef WHEREAND
}
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