Prevent evaluation of backticks while discarding unwanted arguments

after an unknown or failed psql backslash command, and also while
discarding "extra" arguments of a putatively valid backslash command.
In the case of an unknown/failed command, make sure we discard the
whole rest of the line, rather than trying to resume at the next
backslash.  Per discussion with Thomer Gil.

diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index c6ad507..6388f20 100644 (file)
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2000-2004, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/bin/psql/command.c,v 1.137 2004/11/30 20:00:34 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/psql/command.c,v 1.138 2004/12/19 19:39:47 tgl Exp $
  */
 #include "postgres_fe.h"
 #include "command.h"
@@ -127,13 +127,23 @@ HandleSlashCmds(PsqlScanState scan_state,
                status = CMD_ERROR;
        }
 
-       /* eat the rest of the options, if any */
-       while ((arg = psql_scan_slash_option(scan_state,
-                                                                                OT_NORMAL, NULL, false)))
+       if (status != CMD_ERROR)
        {
-               if (status != CMD_ERROR)
+               /* eat any remaining arguments after a valid command */
+               /* note we suppress evaluation of backticks here */
+               while ((arg = psql_scan_slash_option(scan_state,
+                                                                                        OT_VERBATIM, NULL, false)))
+               {
                        psql_error("\\%s: extra argument \"%s\" ignored\n", cmd, arg);
-               free(arg);
+                       free(arg);
+               }
+       }
+       else
+       {
+               /* silently throw away rest of line after an erroneous command */
+               while ((arg = psql_scan_slash_option(scan_state,
+                                                                                        OT_WHOLE_LINE, NULL, false)))
+                       free(arg);
        }
 
        /* if there is a trailing \\, swallow it */

diff --git a/src/bin/psql/psqlscan.h b/src/bin/psql/psqlscan.h
index a4cb945..7b506a5 100644 (file)
--- a/src/bin/psql/psqlscan.h
+++ b/src/bin/psql/psqlscan.h
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2000-2004, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/bin/psql/psqlscan.h,v 1.3 2004/08/29 05:06:54 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/psql/psqlscan.h,v 1.4 2004/12/19 19:39:47 tgl Exp $
  */
 #ifndef PSQLSCAN_H
 #define PSQLSCAN_H
@@ -32,7 +32,8 @@ enum slash_option_type
        OT_SQLID,                                       /* treat as SQL identifier */
        OT_SQLIDHACK,                           /* SQL identifier, but don't downcase */
        OT_FILEPIPE,                            /* it's a filename or pipe */
-       OT_WHOLE_LINE                           /* just snarf the rest of the line */
+       OT_WHOLE_LINE,                          /* just snarf the rest of the line */
+       OT_VERBATIM                                     /* literal (no backticks or variables) */
 };
 
 

diff --git a/src/bin/psql/psqlscan.l b/src/bin/psql/psqlscan.l
index 6311ffa..de73895 100644 (file)
--- a/src/bin/psql/psqlscan.l
+++ b/src/bin/psql/psqlscan.l
@@ -31,7 +31,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/bin/psql/psqlscan.l,v 1.7 2004/08/29 04:13:02 momjian Exp $
+ *       $PostgreSQL: pgsql/src/bin/psql/psqlscan.l,v 1.8 2004/12/19 19:39:47 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -723,24 +723,38 @@ other                     .
                                }
 
 "`"                            {
-                                       *option_quote = '`';
-                                       BEGIN(xslashbackquote);
+                                       if (option_type == OT_VERBATIM)
+                                       {
+                                               /* in verbatim mode, backquote is not special */
+                                               ECHO;
+                                               BEGIN(xslashdefaultarg);
+                                       }
+                                       else
+                                       {
+                                               *option_quote = '`';
+                                               BEGIN(xslashbackquote);
+                                       }
                                }
 
 :[A-Za-z0-9_]* {
                                        /* Possible psql variable substitution */
-                                       const char *value;
+                                       if (option_type == OT_VERBATIM)
+                                               ECHO;
+                                       else
+                                       {
+                                               const char *value;
 
-                                       value = GetVariable(pset.vars, yytext + 1);
+                                               value = GetVariable(pset.vars, yytext + 1);
 
-                                       /*
-                                        * The variable value is just emitted without any
-                                        * further examination.  This is consistent with the
-                                        * pre-8.0 code behavior, if not with the way that
-                                        * variables are handled outside backslash commands.
-                                        */
-                                       if (value)
-                                               appendPQExpBufferStr(output_buf, value);
+                                               /*
+                                                * The variable value is just emitted without any
+                                                * further examination.  This is consistent with the
+                                                * pre-8.0 code behavior, if not with the way that
+                                                * variables are handled outside backslash commands.
+                                                */
+                                               if (value)
+                                                       appendPQExpBufferStr(output_buf, value);
+                                       }
 
                                        *option_quote = ':';