From 1b5e0143b51b672672e8256dc7e8f31f41ebc88f Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Fri, 20 Aug 2004 16:07:15 +0000
Subject: [PATCH] This patch allows pg_restore to recognize $-quotes in SQL
queries. It will treat any unquoted string that starts with a $ and has no
preceding identifier chars as a potential $-quote tag, it then makes sure
that the tag chars are valid. If so, it processes the $-quote.
Philip Warner
---
src/bin/pg_dump/pg_backup_archiver.h | 7 +-
src/bin/pg_dump/pg_backup_db.c | 266 ++++++++++++++++++++-------
2 files changed, 201 insertions(+), 72 deletions(-)
diff --git a/src/bin/pg_dump/pg_backup_archiver.h b/src/bin/pg_dump/pg_backup_archiver.h
index 7466feab0bb..7f6740376e7 100644
--- a/src/bin/pg_dump/pg_backup_archiver.h
+++ b/src/bin/pg_dump/pg_backup_archiver.h
@@ -17,7 +17,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/bin/pg_dump/pg_backup_archiver.h,v 1.58 2004/04/22 02:39:10 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_dump/pg_backup_archiver.h,v 1.59 2004/08/20 16:07:15 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -137,7 +137,9 @@ typedef enum
SQL_SCAN = 0,
SQL_IN_SQL_COMMENT,
SQL_IN_EXT_COMMENT,
- SQL_IN_QUOTE
+ SQL_IN_QUOTE,
+ SQL_IN_DOLLARTAG,
+ SQL_IN_DOLLARQUOTE
} sqlparseState;
typedef struct
@@ -147,6 +149,7 @@ typedef struct
char lastChar;
char quoteChar;
int braceDepth;
+ PQExpBuffer tagBuf;
} sqlparseInfo;
typedef struct _archiveHandle
diff --git a/src/bin/pg_dump/pg_backup_db.c b/src/bin/pg_dump/pg_backup_db.c
index df2f8af3ff2..984c2f844c3 100644
--- a/src/bin/pg_dump/pg_backup_db.c
+++ b/src/bin/pg_dump/pg_backup_db.c
@@ -5,7 +5,7 @@
* Implements the basic DB functions used by the archiver.
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/bin/pg_dump/pg_backup_db.c,v 1.53 2004/04/22 02:39:10 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_dump/pg_backup_db.c,v 1.54 2004/08/20 16:07:15 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -37,6 +37,8 @@ static void notice_processor(void *arg, const char *message);
static char *_sendSQLLine(ArchiveHandle *AH, char *qry, char *eos);
static char *_sendCopyLine(ArchiveHandle *AH, char *qry, char *eos);
+static int _isIdentChar(char c);
+static int _isDQChar(char c, int atStart);
static int
_parse_version(ArchiveHandle *AH, const char *versionString)
@@ -416,6 +418,9 @@ static char *
_sendSQLLine(ArchiveHandle *AH, char *qry, char *eos)
{
int pos = 0; /* Current position */
+ char *sqlPtr;
+ int consumed;
+ int startDT = 0;
/*
* The following is a mini state machine to assess the end of an SQL
@@ -433,88 +438,174 @@ _sendSQLLine(ArchiveHandle *AH, char *qry, char *eos)
appendPQExpBufferChar(AH->sqlBuf, qry[pos]);
/* fprintf(stderr, " %c",qry[pos]); */
- switch (AH->sqlparse.state)
+ /* Loop until character consumed */
+ do
{
+ /* If a character needs to be scanned in a different state,
+ * consumed can be set to 0 to avoid advancing. Care must
+ * be taken to ensure internal state is not damaged.
+ */
+ consumed = 1;
- case SQL_SCAN: /* Default state == 0, set in _allocAH */
- if (qry[pos] == ';' && AH->sqlparse.braceDepth == 0)
+ switch (AH->sqlparse.state)
{
- /* Send It & reset the buffer */
-
- /*
- * fprintf(stderr, " sending: '%s'\n\n",
- * AH->sqlBuf->data);
+
+ case SQL_SCAN: /* Default state == 0, set in _allocAH */
+ if (qry[pos] == ';' && AH->sqlparse.braceDepth == 0)
+ {
+ /* We've got the end of a statement.
+ * Send It & reset the buffer.
+ */
+
+ /*
+ * fprintf(stderr, " sending: '%s'\n\n",
+ * AH->sqlBuf->data);
+ */
+ ExecuteSqlCommand(AH, AH->sqlBuf, "could not execute query", false);
+ resetPQExpBuffer(AH->sqlBuf);
+ AH->sqlparse.lastChar = '\0';
+
+ /*
+ * Remove any following newlines - so that embedded
+ * COPY commands don't get a starting newline.
+ */
+ pos++;
+ for (; pos < (eos - qry) && qry[pos] == '\n'; pos++);
+
+ /* We've got our line, so exit */
+ return qry + pos;
+ }
+ else
+ {
+ /*
+ * Look for normal boring quote chars, or dollar-quotes. We make
+ * the assumption that $-quotes will not have an ident character
+ * before them in all pg_dump output.
+ */
+ if ( qry[pos] == '"'
+ || qry[pos] == '\''
+ || ( qry[pos] == '$' && _isIdentChar(AH->sqlparse.lastChar) == 0 )
+ )
+ {
+ /* fprintf(stderr,"[startquote]\n"); */
+ AH->sqlparse.state = SQL_IN_QUOTE;
+ AH->sqlparse.quoteChar = qry[pos];
+ AH->sqlparse.backSlash = 0;
+ if (qry[pos] == '$')
+ {
+ /* override the state */
+ AH->sqlparse.state = SQL_IN_DOLLARTAG;
+ /* Used for checking first char of tag */
+ startDT = 1;
+ /* We store the tag for later comparison. */
+ AH->sqlparse.tagBuf = createPQExpBuffer();
+ /* Get leading $ */
+ appendPQExpBufferChar(AH->sqlparse.tagBuf, qry[pos]);
+ }
+ }
+ else if (qry[pos] == '-' && AH->sqlparse.lastChar == '-')
+ AH->sqlparse.state = SQL_IN_SQL_COMMENT;
+ else if (qry[pos] == '*' && AH->sqlparse.lastChar == '/')
+ AH->sqlparse.state = SQL_IN_EXT_COMMENT;
+ else if (qry[pos] == '(')
+ AH->sqlparse.braceDepth++;
+ else if (qry[pos] == ')')
+ AH->sqlparse.braceDepth--;
+
+ AH->sqlparse.lastChar = qry[pos];
+ }
+ break;
+
+ case SQL_IN_DOLLARTAG:
+
+ /* Like a quote, we look for a closing char *but* we only
+ * allow a very limited set of contained chars, and no escape chars.
+ * If invalid chars are found, we abort tag processing.
*/
- ExecuteSqlCommand(AH, AH->sqlBuf, "could not execute query", false);
- resetPQExpBuffer(AH->sqlBuf);
- AH->sqlparse.lastChar = '\0';
+
+ if (qry[pos] == '$')
+ {
+ /* fprintf(stderr,"[endquote]\n"); */
+ /* Get trailing $ */
+ appendPQExpBufferChar(AH->sqlparse.tagBuf, qry[pos]);
+ AH->sqlparse.state = SQL_IN_DOLLARQUOTE;
+ }
+ else
+ {
+ if ( _isDQChar(qry[pos], startDT) )
+ {
+ /* Valid, so add */
+ appendPQExpBufferChar(AH->sqlparse.tagBuf, qry[pos]);
+ }
+ else
+ {
+ /* Jump back to 'scan' state, we're not really in a tag,
+ * and valid tag chars do not include the various chars
+ * we look for in this state machine, so it's safe to just
+ * jump from this state back to SCAN. We set consumed = 0
+ * so that this char gets rescanned in new state.
+ */
+ destroyPQExpBuffer(AH->sqlparse.tagBuf);
+ AH->sqlparse.state = SQL_SCAN;
+ consumed = 0;
+ }
+ }
+ startDT = 0;
+ break;
+
+ case SQL_IN_DOLLARQUOTE:
/*
- * Remove any following newlines - so that embedded
- * COPY commands don't get a starting newline.
+ * Comparing the entire string backwards each time is NOT efficient,
+ * but dollar quotes in pg_dump are small and the code is a lot simpler.
*/
- pos++;
- for (; pos < (eos - qry) && qry[pos] == '\n'; pos++);
-
- /* We've got our line, so exit */
- return qry + pos;
- }
- else
- {
- if (qry[pos] == '"' || qry[pos] == '\'')
+ sqlPtr = AH->sqlBuf->data + AH->sqlBuf->len - AH->sqlparse.tagBuf->len;
+
+ if (strncmp(AH->sqlparse.tagBuf->data, sqlPtr, AH->sqlparse.tagBuf->len) == 0) {
+ /* End of $-quote */
+ AH->sqlparse.state = SQL_SCAN;
+ destroyPQExpBuffer(AH->sqlparse.tagBuf);
+ }
+ break;
+
+ case SQL_IN_SQL_COMMENT:
+ if (qry[pos] == '\n')
+ AH->sqlparse.state = SQL_SCAN;
+ break;
+
+ case SQL_IN_EXT_COMMENT:
+ if (AH->sqlparse.lastChar == '*' && qry[pos] == '/')
+ AH->sqlparse.state = SQL_SCAN;
+ break;
+
+ case SQL_IN_QUOTE:
+
+ if (!AH->sqlparse.backSlash && AH->sqlparse.quoteChar == qry[pos])
{
- /* fprintf(stderr,"[startquote]\n"); */
- AH->sqlparse.state = SQL_IN_QUOTE;
- AH->sqlparse.quoteChar = qry[pos];
- AH->sqlparse.backSlash = 0;
+ /* fprintf(stderr,"[endquote]\n"); */
+ AH->sqlparse.state = SQL_SCAN;
}
- else if (qry[pos] == '-' && AH->sqlparse.lastChar == '-')
- AH->sqlparse.state = SQL_IN_SQL_COMMENT;
- else if (qry[pos] == '*' && AH->sqlparse.lastChar == '/')
- AH->sqlparse.state = SQL_IN_EXT_COMMENT;
- else if (qry[pos] == '(')
- AH->sqlparse.braceDepth++;
- else if (qry[pos] == ')')
- AH->sqlparse.braceDepth--;
-
- AH->sqlparse.lastChar = qry[pos];
- }
- break;
-
- case SQL_IN_SQL_COMMENT:
- if (qry[pos] == '\n')
- AH->sqlparse.state = SQL_SCAN;
- break;
-
- case SQL_IN_EXT_COMMENT:
- if (AH->sqlparse.lastChar == '*' && qry[pos] == '/')
- AH->sqlparse.state = SQL_SCAN;
- break;
-
- case SQL_IN_QUOTE:
- if (!AH->sqlparse.backSlash && AH->sqlparse.quoteChar == qry[pos])
- {
- /* fprintf(stderr,"[endquote]\n"); */
- AH->sqlparse.state = SQL_SCAN;
- }
- else
- {
-
- if (qry[pos] == '\\')
+ else
{
- if (AH->sqlparse.lastChar == '\\')
- AH->sqlparse.backSlash = !AH->sqlparse.backSlash;
+
+ if (qry[pos] == '\\')
+ {
+ if (AH->sqlparse.lastChar == '\\')
+ AH->sqlparse.backSlash = !AH->sqlparse.backSlash;
+ else
+ AH->sqlparse.backSlash = 1;
+ }
else
- AH->sqlparse.backSlash = 1;
+ AH->sqlparse.backSlash = 0;
}
- else
- AH->sqlparse.backSlash = 0;
- }
- break;
+ break;
+
+ }
- }
- AH->sqlparse.lastChar = qry[pos];
- /* fprintf(stderr, "\n"); */
+ } while (consumed == 0);
+
+ AH->sqlparse.lastChar = qry[pos];
+ /* fprintf(stderr, "\n"); */
}
/*
@@ -759,3 +850,38 @@ CommitTransactionXref(ArchiveHandle *AH)
destroyPQExpBuffer(qry);
}
+
+static int _isIdentChar(char c)
+{
+ if ( (c >= 'a' && c <= 'z')
+ || (c >= 'A' && c <= 'Z')
+ || (c >= '0' && c <= '9')
+ || (c == '_')
+ || (c == '$')
+ || (c >= '\200' && c <= '\377')
+ )
+ {
+ return 1;
+ }
+ else
+ {
+ return 0;
+ }
+}
+
+static int _isDQChar(char c, int atStart)
+{
+ if ( (c >= 'a' && c <= 'z')
+ || (c >= 'A' && c <= 'Z')
+ || (c == '_')
+ || (atStart == 0 && c >= '0' && c <= '9')
+ || (c >= '\200' && c <= '\377')
+ )
+ {
+ return 1;
+ }
+ else
+ {
+ return 0;
+ }
+}
--
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