diff options
Diffstat (limited to 'src/backend/utils/adt')
-rw-r--r-- | src/backend/utils/adt/ruleutils.c | 37 | ||||
-rw-r--r-- | src/backend/utils/adt/varlena.c | 112 |
2 files changed, 143 insertions, 6 deletions
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 5a61d2dac00..03e9a28a63b 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -2640,14 +2640,39 @@ pg_get_functiondef(PG_FUNCTION_ARGS) /* * Variables that are marked GUC_LIST_QUOTE were already fully * quoted by flatten_set_variable_args() before they were put - * into the proconfig array; we mustn't re-quote them or we'll - * make a mess. Variables that are not so marked should just - * be emitted as simple string literals. If the variable is - * not known to guc.c, we'll do the latter; this makes it - * unsafe to use GUC_LIST_QUOTE for extension variables. + * into the proconfig array. However, because the quoting + * rules used there aren't exactly like SQL's, we have to + * break the list value apart and then quote the elements as + * string literals. (The elements may be double-quoted as-is, + * but we can't just feed them to the SQL parser; it would do + * the wrong thing with elements that are zero-length or + * longer than NAMEDATALEN.) + * + * Variables that are not so marked should just be emitted as + * simple string literals. If the variable is not known to + * guc.c, we'll do that; this makes it unsafe to use + * GUC_LIST_QUOTE for extension variables. */ if (GetConfigOptionFlags(configitem, true) & GUC_LIST_QUOTE) - appendStringInfoString(&buf, pos); + { + List *namelist; + ListCell *lc; + + /* Parse string into list of identifiers */ + if (!SplitGUCList(pos, ',', &namelist)) + { + /* this shouldn't fail really */ + elog(ERROR, "invalid list syntax in proconfig item"); + } + foreach(lc, namelist) + { + char *curname = (char *) lfirst(lc); + + simple_quote_literal(&buf, curname); + if (lnext(lc)) + appendStringInfoString(&buf, ", "); + } + } else simple_quote_literal(&buf, pos); appendStringInfoChar(&buf, '\n'); diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c index e8500b274dc..87ecf58adeb 100644 --- a/src/backend/utils/adt/varlena.c +++ b/src/backend/utils/adt/varlena.c @@ -3503,6 +3503,118 @@ SplitDirectoriesString(char *rawstring, char separator, } +/* + * SplitGUCList --- parse a string containing identifiers or file names + * + * This is used to split the value of a GUC_LIST_QUOTE GUC variable, without + * presuming whether the elements will be taken as identifiers or file names. + * We assume the input has already been through flatten_set_variable_args(), + * so that we need never downcase (if appropriate, that was done already). + * Nor do we ever truncate, since we don't know the correct max length. + * We disallow embedded whitespace for simplicity (it shouldn't matter, + * because any embedded whitespace should have led to double-quoting). + * Otherwise the API is identical to SplitIdentifierString. + * + * XXX it's annoying to have so many copies of this string-splitting logic. + * However, it's not clear that having one function with a bunch of option + * flags would be much better. + * + * XXX there is a version of this function in src/bin/pg_dump/dumputils.c. + * Be sure to update that if you have to change this. + * + * Inputs: + * rawstring: the input string; must be overwritable! On return, it's + * been modified to contain the separated identifiers. + * separator: the separator punctuation expected between identifiers + * (typically '.' or ','). Whitespace may also appear around + * identifiers. + * Outputs: + * namelist: filled with a palloc'd list of pointers to identifiers within + * rawstring. Caller should list_free() this even on error return. + * + * Returns true if okay, false if there is a syntax error in the string. + */ +bool +SplitGUCList(char *rawstring, char separator, + List **namelist) +{ + char *nextp = rawstring; + bool done = false; + + *namelist = NIL; + + while (scanner_isspace(*nextp)) + nextp++; /* skip leading whitespace */ + + if (*nextp == '\0') + return true; /* allow empty string */ + + /* At the top of the loop, we are at start of a new identifier. */ + do + { + char *curname; + char *endp; + + if (*nextp == '"') + { + /* Quoted name --- collapse quote-quote pairs */ + curname = nextp + 1; + for (;;) + { + endp = strchr(nextp + 1, '"'); + if (endp == NULL) + return false; /* mismatched quotes */ + if (endp[1] != '"') + break; /* found end of quoted name */ + /* Collapse adjacent quotes into one quote, and look again */ + memmove(endp, endp + 1, strlen(endp)); + nextp = endp; + } + /* endp now points at the terminating quote */ + nextp = endp + 1; + } + else + { + /* Unquoted name --- extends to separator or whitespace */ + curname = nextp; + while (*nextp && *nextp != separator && + !scanner_isspace(*nextp)) + nextp++; + endp = nextp; + if (curname == nextp) + return false; /* empty unquoted name not allowed */ + } + + while (scanner_isspace(*nextp)) + nextp++; /* skip trailing whitespace */ + + if (*nextp == separator) + { + nextp++; + while (scanner_isspace(*nextp)) + nextp++; /* skip leading whitespace for next */ + /* we expect another name, so done remains false */ + } + else if (*nextp == '\0') + done = true; + else + return false; /* invalid syntax */ + + /* Now safe to overwrite separator with a null */ + *endp = '\0'; + + /* + * Finished isolating current name --- add it to list + */ + *namelist = lappend(*namelist, curname); + + /* Loop back if we didn't reach end of string */ + } while (!done); + + return true; +} + + /***************************************************************************** * Comparison Functions used for bytea * |