Differences From:

File src/printf.c part of check-in [285929373757b] - Add the %w and %W formatting options for internal printf usage. Use these formatting characters to render wiki. Fix additional problems of unterminated wiki on webpage rendering by using %w. (There are probably more problems yet to be discovered and fixed.) by drh on 2007-11-22 22:55:05. Also file src/printf.c part of check-in [d0305b305a] - Merged mainline into my branch to get the newest application. by aku on 2007-12-05 08:07:46. [view]

To:

File src/printf.c part of check-in [8c3ec00311] - On the printf extension converters (ex: %T, %w) the "alternate form flag" (ex: %#T, %#w) means first read an integer from the argument list and then only process that number of characters from the string or blob that is read next from the argument list. by drh on 2008-02-04 19:07:58. [view]

@@ -149,8 +149,21 @@
 */
 #define etBUFSIZE 500
 
 /*
+** Find the length of a string as long as that length does not
+** exceed N bytes.  If no zero terminator is seen in the first
+** N bytes then return N.  If N is negative, then this routine
+** is an alias for strlen().
+*/
+static int strnlen(const char *z, int N){
+  int n = 0;
+  while( (N-- != 0) && *(z++)!=0 ){ n++; }
+  return n;
+}
+
+
+/*
 ** The root program.  All variations call this core.
 **
 ** INPUTS:
 **   func   This is a pointer to a function taking three arguments
@@ -548,11 +561,12 @@
         bufpt = buf;
         break;
       case etPATH: {
         int i;
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *e = va_arg(ap,char*);
         if( e==0 ){e="";}
-        length = strlen(e);
+        length = strnlen(e, limit);
         zExtra = bufpt = malloc(length+1);
         for( i=0; i<length; i++ ){
           if( e[i]=='\\' ){
             bufpt[i]='/';
@@ -563,29 +577,35 @@
         bufpt[length]='\0';
         break;
       }
       case etSTRING:
-      case etDYNSTRING:
+      case etDYNSTRING: {
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         bufpt = va_arg(ap,char*);
         if( bufpt==0 ){
           bufpt = "";
         }else if( xtype==etDYNSTRING ){
           zExtra = bufpt;
         }
-        length = strlen(bufpt);
+        length = strnlen(bufpt, limit);
         if( precision>=0 && precision<length ) length = precision;
         break;
+      }
       case etBLOB: {
+        int limit = flag_alternateform ? va_arg(ap, int) : -1;
         Blob *pBlob = va_arg(ap, Blob*);
         bufpt = blob_buffer(pBlob);
         length = blob_size(pBlob);
+        if( limit>=0 && limit<length ) length = limit;
         break;
       }
       case etBLOBSQL: {
+        int limit = flag_alternateform ? va_arg(ap, int) : -1;
         Blob *pBlob = va_arg(ap, Blob*);
         char *zOrig = blob_buffer(pBlob);
         int i, j, n, cnt;
         n = blob_size(pBlob);
+        if( limit>=0 && limit<n ) n = limit;
         for(cnt=i=0; i<n; i++){ if( zOrig[i]=='\'' ) cnt++; }
         if( n+cnt+2 > etBUFSIZE ){
           bufpt = zExtra = malloc( n + cnt + 2 );
         }else{
@@ -604,13 +624,15 @@
       case etSQLESCAPE:
       case etSQLESCAPE2: {
         int i, j, n, ch, isnull;
         int needQuote;
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *escarg = va_arg(ap,char*);
         isnull = escarg==0;
         if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
-        for(i=n=0; (ch=escarg[i])!=0; i++){
-          if( ch=='\'' )  n++;
+        if( limit<0 ) limit = strlen(escarg);
+        for(i=n=0; i<limit; i++){
+          if( escarg[i]=='\'' )  n++;
         }
         needQuote = !isnull && xtype==etSQLESCAPE2;
         n += i + 1 + needQuote*2;
         if( n>etBUFSIZE ){
@@ -620,10 +642,10 @@
           bufpt = buf;
         }
         j = 0;
         if( needQuote ) bufpt[j++] = '\'';
-        for(i=0; (ch=escarg[i])!=0; i++){
-          bufpt[j++] = ch;
+        for(i=0; i<limit; i++){
+          bufpt[j++] = ch = escarg[i];
           if( ch=='\'' ) bufpt[j++] = ch;
         }
         if( needQuote ) bufpt[j++] = '\'';
         bufpt[j] = 0;
@@ -631,43 +653,48 @@
         if( precision>=0 && precision<length ) length = precision;
         break;
       }
       case etHTMLIZE: {
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *zMem = va_arg(ap,char*);
         if( zMem==0 ) zMem = "";
-        zExtra = bufpt = htmlize(zMem, -1);
+        zExtra = bufpt = htmlize(zMem, limit);
         length = strlen(bufpt);
         if( precision>=0 && precision<length ) length = precision;
         break;
       }
       case etHTTPIZE: {
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *zMem = va_arg(ap,char*);
         if( zMem==0 ) zMem = "";
-        zExtra = bufpt = httpize(zMem, -1);
+        zExtra = bufpt = httpize(zMem, limit);
         length = strlen(bufpt);
         if( precision>=0 && precision<length ) length = precision;
         break;
       }
       case etURLIZE: {
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *zMem = va_arg(ap,char*);
         if( zMem==0 ) zMem = "";
-        zExtra = bufpt = urlize(zMem, -1);
+        zExtra = bufpt = urlize(zMem, limit);
         length = strlen(bufpt);
         if( precision>=0 && precision<length ) length = precision;
         break;
       }
       case etFOSSILIZE: {
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *zMem = va_arg(ap,char*);
         if( zMem==0 ) zMem = "";
-        zExtra = bufpt = fossilize(zMem, -1);
+        zExtra = bufpt = fossilize(zMem, limit);
         length = strlen(bufpt);
         if( precision>=0 && precision<length ) length = precision;
         break;
       }
       case etWIKISTR: {
+        int limit = flag_alternateform ? va_arg(ap,int) : -1;
         char *zWiki = va_arg(ap, char*);
         Blob wiki;
-        blob_init(&wiki, zWiki, -1);
+        blob_init(&wiki, zWiki, limit);
         wiki_convert(&wiki, pBlob, WIKI_INLINE);
         blob_reset(&wiki);
         length = width = 0;
         break;