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

diff --git a/src/bin/pg_dump/pg_backup_archiver.h b/src/bin/pg_dump/pg_backup_archiver.h
index 7466feab0bb4391157bd926bc4a5e94800c0ab61..7f6740376e78ec9fa6e6750774890fa98dc6cccb 100644 (file)
--- 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 df2f8af3ff2bbc9d03104e4b4e5a24f85a71eab4..984c2f844c3bb0fa10a8000fa65dcbded54939d5 100644 (file)
--- 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;
+   }
+}