* Peter Eisentraut <[EMAIL PROTECTED]> [001115 10:26]:
> Larry Rosenman writes:
> 
> > Ok, so what I think(?) needs to happen is the FIXME: tag needs to be
> > handled.  We need to code a version of src/backend/parser/scansup.c
> > that doesn't use palloc, and also strips the apostrophes from the
> > front and end of the string?  This doesn't look that hard. Do I have 
> > "permission" to play with it, and submit a patch when I've got it
> > fixed? 
> 
> Some background information:  The current
> 
>   name = value
> 
> syntax is lexically compatible with the syntax of the SET command.  
> Therefore you can't have "funny" characters in 'value' unless
> single-quoted.
I added period(.), hyphen(-), and underscore(_).
> 
> Now in the context of the config file this seems overly restrictive.  
> Therefore I'd agree that we relax that a bit and allow more characters to
> go into 'value' unquoted.  I'm not quite sure which, but to prevent
> confusion I'd prefer no semicolons, whitespace, or equal signs, possibly
> others.
> 
> This would require making 'value' a different token type from 'name',
> because the latter should not accept these characters.
done, as GUC_UNQUOTED_STRING.
> 
> Additionally, the FIXME ought to be done.  I'd prefer it if it accepted
> the exact same escapes and all as does the SQL parser/scanner.  So it
> ought to be a copy and paste from scansup.c.  I'm not excited about
> allowing double-quotes though.
Done.  Added as GUC_scanstr. 

Here is a patch.  Comments? 

Index: src/backend/utils/misc/guc-file.l
===================================================================
RCS file: /home/projects/pgsql/cvsroot/pgsql/src/backend/utils/misc/guc-file.l,v
retrieving revision 1.4
diff -c -r1.4 guc-file.l
*** src/backend/utils/misc/guc-file.l   2000/07/27 19:49:18     1.4
--- src/backend/utils/misc/guc-file.l   2000/11/15 18:13:20
***************
*** 16,21 ****
--- 16,22 ----
  #include <sys/stat.h>
  #include <unistd.h>
  #include <errno.h>
+ #include <ctype.h>
  
  #include "miscadmin.h"
  #include "storage/fd.h"
***************
*** 32,37 ****
--- 33,39 ----
        GUC_INTEGER = 3,
        GUC_REAL = 4,
        GUC_EQUALS = 5,
+       GUC_UNQUOTED_STRING = 6,
        GUC_EOL = 99,
        GUC_ERROR = 100
  };
***************
*** 45,51 ****
  
  /* prototype, so compiler is happy with our high warnings setting */
  int GUC_yylex(void);
! 
  %}
  
  SIGN            ("-"|"+")
--- 47,53 ----
  
  /* prototype, so compiler is happy with our high warnings setting */
  int GUC_yylex(void);
! char *GUC_scanstr(char *);
  %}
  
  SIGN            ("-"|"+")
***************
*** 69,76 ****
   * work right. Now there are no string options, and if there were then
   * the unquoted (`ID') tokens should still work. Of course this only
   * affects the configuration file.
   */
! STRING          \'([^'\n]|\\.)*'
  
  %%
  
--- 71,83 ----
   * work right. Now there are no string options, and if there were then
   * the unquoted (`ID') tokens should still work. Of course this only
   * affects the configuration file.
+  * LER 14NOV2000: I set it up to accept either a quoted string or a string
+  * in apostrophes.  I then kill off the 1st and last characters.  There is 
+  * no special handling for doubled terminators or 'C' escapes. 
+  * this allows most other characters to be used.
   */
! UNQUOTED_STRING {LETTER}({LETTER_OR_DIGIT}|[-._])*
! STRING          (\'|\")([^'"\n]|\\.)*(\'|\")
  
  %%
  
***************
*** 80,85 ****
--- 87,93 ----
  
  {ID}            return GUC_ID;
  {STRING}        return GUC_STRING;
+ {UNQUOTED_STRING} return GUC_UNQUOTED_STRING;
  {INTEGER}       return GUC_INTEGER;
  {REAL}          return GUC_REAL;
  =               return GUC_EQUALS;
***************
*** 210,220 ****
                  if (token == GUC_EQUALS)
                      token = yylex();
  
!                 if (token != GUC_ID && token != GUC_STRING && token != GUC_INTEGER 
&& token != GUC_REAL)
                      goto parse_error;
                  opt_value = strdup(yytext);
                                if (opt_value == NULL)
                                        goto out_of_memory;
                  parse_state = 2;
                  break;
  
--- 218,239 ----
                  if (token == GUC_EQUALS)
                      token = yylex();
  
!                 if (token != GUC_ID && token != GUC_STRING && token != GUC_INTEGER 
&& token != GUC_REAL && token != GUC_UNQUOTED_STRING)
                      goto parse_error;
                  opt_value = strdup(yytext);
                                if (opt_value == NULL)
                                        goto out_of_memory;
+               if (token == GUC_STRING)
+               {
+                       /* remove the beginning and ending quote/apostrophe */
+                       /* first: shift the whole shooting match down one
+                       character */
+                       memmove(opt_value,opt_value+1,strlen(opt_value)-1);
+                       /* second: null out the 2 characters we shifted */
+                         opt_value[strlen(opt_value)-2]='\0';
+                       /* do the escape thing.  free()'s the strdup above */
+                       opt_value=GUC_scanstr(opt_value);
+               }
                  parse_state = 2;
                  break;
  
***************
*** 283,286 ****
--- 302,400 ----
  yywrap(void)
  {
        return 1;
+ }
+ 
+ /* ----------------
+  *            scanstr
+  *
+  * if the string passed in has escaped codes, map the escape codes to actual
+  * chars
+  *
+  * the string returned is palloc'd and should eventually be pfree'd by the
+  * caller!
+  * ----------------
+  */
+ 
+ char *
+ GUC_scanstr(char *s)
+ {
+       char       *newStr;
+       int                     len,
+                               i,
+                               j;
+ 
+       if (s == NULL || s[0] == '\0')
+       {
+               if (s != NULL) free (s);
+               return strdup("");
+ 
+       }
+       len = strlen(s);
+ 
+       newStr = malloc(len + 1);       /* string cannot get longer */
+ 
+       for (i = 0, j = 0; i < len; i++)
+       {
+               if (s[i] == '\'')
+               {
+ 
+                       /*
+                        * Note: if scanner is working right, unescaped quotes can
+                        * only appear in pairs, so there should be another character.
+                        */
+                       i++;
+                       newStr[j] = s[i];
+               }
+               else if (s[i] == '\\')
+               {
+                       i++;
+                       switch (s[i])
+                       {
+                               case 'b':
+                                       newStr[j] = '\b';
+                                       break;
+                               case 'f':
+                                       newStr[j] = '\f';
+                                       break;
+                               case 'n':
+                                       newStr[j] = '\n';
+                                       break;
+                               case 'r':
+                                       newStr[j] = '\r';
+                                       break;
+                               case 't':
+                                       newStr[j] = '\t';
+                                       break;
+                               case '0':
+                               case '1':
+                               case '2':
+                               case '3':
+                               case '4':
+                               case '5':
+                               case '6':
+                               case '7':
+                                       {
+                                               int                     k;
+                                               long            octVal = 0;
+ 
+                                               for (k = 0;
+                                                        s[i + k] >= '0' && s[i + k] 
+<= '7' && k < 3;
+                                                        k++)
+                                                       octVal = (octVal << 3) + (s[i 
++ k] - '0');
+                                               i += k - 1;
+                                               newStr[j] = ((char) octVal);
+                                       }
+                                       break;
+                               default:
+                                       newStr[j] = s[i];
+                                       break;
+                       }                                       /* switch */
+               }                                               /* s[i] == '\\' */
+               else
+                       newStr[j] = s[i];
+               j++;
+       }
+       newStr[j] = '\0';
+       free(s);
+       return newStr;
  }

-- 
Larry Rosenman                      http://www.lerctr.org/~ler
Phone: +1 972-414-9812 (voice) Internet: [EMAIL PROTECTED]
US Mail: 1905 Steamboat Springs Drive, Garland, TX 75044-6749

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