dumputils.c

PostgreSQL7.4.6 for Linux

									  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, "REVOKE ALL 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;
}

/*
 * Deconstruct an ACL array (or actually any 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.
 */
static bool
parseAclArray(const char *acls, 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(acls);
	if (inputlen < 2 || acls[0] != '{' || acls[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);

	acls++;						/* advance over initial '{' */
	curitem = 0;
	while (*acls != '}')
	{
		if (*acls == '\0')
			return false;		/* premature end of string */
		items[curitem] = strings;
		while (*acls != '}' && *acls != ',')
		{
			if (*acls == '\0')
				return false;	/* premature end of string */
			if (*acls != '"')
				*strings++ = *acls++;	/* copy unquoted data */
			else
			{
				/* process quoted substring */
				acls++;
				while (*acls != '"')
				{
					if (*acls == '\0')
						return false;	/* premature end of string */
					if (*acls == '\\')
					{
						acls++;
						if (*acls == '\0')
							return false;		/* premature end of string */
					}
					*strings++ = *acls++;		/* copy quoted data */
				}
				acls++;
			}
		}
		*strings++ = '\0';
		if (*acls == ',')
			acls++;
		curitem++;
	}
	if (acls[1] != '\0')
		return false;			/* bogus syntax (embedded '}') */
	*nitems = curitem;
	return true;
}

/*
 * 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,
			 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);

	/* 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) \
	if ((pos = strchr(eqpos + 1, code))) \
	{ \
		if (*(pos + 1) == '*') \
		{ \
			AddAcl(privswgo, keywd); \
			all_without_go = false; \
		} \
		else \
		{ \
			AddAcl(privs, keywd); \
			all_with_go = false; \
		} \
	} \
	else \
		all_with_go = all_without_go = false

	resetPQExpBuffer(privs);
	resetPQExpBuffer(privswgo);

	if (strcmp(type, "TABLE") == 0)
	{
		CONVERT_PRIV('a', "INSERT");
		CONVERT_PRIV('r', "SELECT");
		CONVERT_PRIV('R', "RULE");

		if (remoteVersion >= 70200)
		{
			CONVERT_PRIV('w', "UPDATE");
			CONVERT_PRIV('d', "DELETE");
			CONVERT_PRIV('x', "REFERENCES");
			CONVERT_PRIV('t', "TRIGGER");
		}
		else
		{
			/* 7.0 and 7.1 have a simpler worldview */
			CONVERT_PRIV('w', "UPDATE,DELETE");
		}
	}
	else if (strcmp(type, "FUNCTION") == 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('T', "TEMPORARY");
	}
	else
		abort();

#undef CONVERT_PRIV

	if (all_with_go)
	{
		resetPQExpBuffer(privs);
		printfPQExpBuffer(privswgo, "ALL");
	}
	else if (all_without_go)
	{
		resetPQExpBuffer(privswgo);
		printfPQExpBuffer(privs, "ALL");
	}

	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)
{
	if (aclbuf->len > 0)
		appendPQExpBufferChar(aclbuf, ',');
	appendPQExpBuffer(aclbuf, "%s", keyword);
}