Hello David,
+Agree. However, it would nice to update the sentence below if I understand
it correctly.
"+ Comments, whitespace and continuations are handled in the same way as
in" pg_hba.conf
In the attached v3, I've tried to clarify comments and doc about
tokenization rules relating to comments, strings and continuations.
--
Fabien.
diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index 5f1eec78fb..5d6412de9b 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -77,13 +77,16 @@
The general format of the <filename>pg_hba.conf</filename> file is
a set of records, one per line. Blank lines are ignored, as is any
text after the <literal>#</literal> comment character.
- Records cannot be continued across lines.
+ Lines ending with a backslash are logically continued on the next
+ line, so a record can span several lines.
A record is made
up of a number of fields which are separated by spaces and/or tabs.
Fields can contain white space if the field value is double-quoted.
Quoting one of the keywords in a database, user, or address field (e.g.,
<literal>all</literal> or <literal>replication</literal>) makes the word lose its special
meaning, and just match a database, user, or host with that name.
+ If a continuation occurs within a quoted text or a comment,
+ the quoted text or comment are continued.
</para>
<para>
@@ -821,7 +824,7 @@ local db1,db2,@demodbs all md5
<synopsis>
<replaceable>map-name</replaceable> <replaceable>system-username</replaceable> <replaceable>database-username</replaceable>
</synopsis>
- Comments and whitespace are handled in the same way as in
+ Comments, whitespace and continuations are handled in the same way as in
<filename>pg_hba.conf</filename>. The
<replaceable>map-name</replaceable> is an arbitrary name that will be used to
refer to this mapping in <filename>pg_hba.conf</filename>. The other
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index da5189a4fa..e88758c5aa 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -166,11 +166,17 @@ pg_isblank(const char c)
/*
* Grab one token out of the string pointed to by *lineptr.
*
- * Tokens are strings of non-blank
- * characters bounded by blank characters, commas, beginning of line, and
- * end of line. Blank means space or tab. Tokens can be delimited by
- * double quotes (this allows the inclusion of blanks, but not newlines).
- * Comments (started by an unquoted '#') are skipped.
+ * Tokens are strings of non-blank characters bounded by blank characters,
+ * commas, beginning of line, and end of line. Blank means space or tab.
+ *
+ * Tokens can be delimited by double quotes (this allows the inclusion of
+ * blanks or '#', but not newlines). If a continuations occured within the
+ * quoted text, the quoted text is continued on the next line. There is no
+ * escape mechanism, thus character '"' cannot be part of a token.
+ *
+ * Comments (started by an unquoted '#') are skipped, i.e. the remainder
+ * of the line is ignored. If a line with a comment was backslash-continued,
+ * the continuated text is part of the comment, thus ignored as well.
*
* The token, if any, is returned at *buf (a buffer of size bufsz), and
* *lineptr is advanced past the token.
@@ -486,8 +492,43 @@ tokenize_file(const char *filename, FILE *file, List **tok_lines, int elevel)
char *lineptr;
List *current_line = NIL;
char *err_msg = NULL;
+ char *cur = rawline;
+ int len = sizeof(rawline);
+ int continuations = 0;
- if (!fgets(rawline, sizeof(rawline), file))
+ /* read input and handle simplistic backslash continuations */
+ while ((cur = fgets(cur, len, file)) != NULL)
+ {
+ int curlen = strlen(cur);
+ char *curend = cur + curlen - 1;
+
+ if (curlen == len - 1)
+ {
+ /* Line too long! */
+ ereport(elevel,
+ (errcode(ERRCODE_CONFIG_FILE_ERROR),
+ errmsg("authentication file line too long"),
+ errcontext("line %d of configuration file \"%s\"",
+ line_number + continuations, filename)));
+ err_msg = "authentication file line too long";
+ }
+
+ /* Strip trailing linebreak from rawline */
+ while (curend >= cur && (*curend == '\n' || *curend == '\r'))
+ *curend-- = '\0';
+
+ /* empty or not a continuation, we are done */
+ if (curend < cur || *curend != '\\')
+ break;
+
+ /* else we have a continuation, just remove it and loop */
+ continuations++;
+ *curend = '\0';
+ len -= (curend - cur);
+ cur = curend;
+ }
+
+ if (cur == NULL)
{
int save_errno = errno;
@@ -501,21 +542,6 @@ tokenize_file(const char *filename, FILE *file, List **tok_lines, int elevel)
filename, strerror(save_errno));
rawline[0] = '\0';
}
- if (strlen(rawline) == MAX_LINE - 1)
- {
- /* Line too long! */
- ereport(elevel,
- (errcode(ERRCODE_CONFIG_FILE_ERROR),
- errmsg("authentication file line too long"),
- errcontext("line %d of configuration file \"%s\"",
- line_number, filename)));
- err_msg = "authentication file line too long";
- }
-
- /* Strip trailing linebreak from rawline */
- lineptr = rawline + strlen(rawline) - 1;
- while (lineptr >= rawline && (*lineptr == '\n' || *lineptr == '\r'))
- *lineptr-- = '\0';
/* Parse fields */
lineptr = rawline;
@@ -543,7 +569,7 @@ tokenize_file(const char *filename, FILE *file, List **tok_lines, int elevel)
*tok_lines = lappend(*tok_lines, tok_line);
}
- line_number++;
+ line_number += continuations + 1;
}
MemoryContextSwitchTo(oldcxt);
