Reinstate NULL FILE * checks in 1991/dds

1991/dds/dds.c

@@ -11,8 +11,8 @@ aP1Q*aHb%FN1\nQm>::::aHC%VP3Q>bupj)hfut)c**aHb%JD12JON1!Qjg)a%LN1UP1D12JIQUa\
 P1HL%IQ*m>aN2!N2\nP2Q<fmtf!m,,aHC%MN1!N2>P2Q>aN2\nP2Hbdd!.Xop.fssps!.Xop.sfu\
 vso.uzqf!.Xop.jnqmjdju.gvodujpo.efdmbsbujpo!b/d";int k;char R[4][99]
 ;main(c,v)char**v;{char*p,*r,*q;for(q=s;*q;q++)*q>' '&&(*q)--;{FILE*i=fopen(v
-[1],"r"),*o=fopen(q-3,"w");for(p=s;;p++)switch(*p++){B'M':Q(k=fgetc(i))!=EOF
-&&k!=*p)*r++=k;if(k==EOF){fputs("}}\n",o);fclose(o);return system(q-69);}*r=0
-B'P':while(*p!='`')fputc(*p++,o)B'O':Q*r)fputc(*r++,o);p--B'C':k=0;Q k<*p-'0'
-)(*r++=fgetc(i),k++);*r=0 B'I':k= *p;if(**R==k)goto G B'G':k= *p;G:p=s;while(
-*p!='$'||p[1]!= k)p++;p++B'N':R[*p-'0'][0]++;}}}
+[1],"r"),*o=fopen(q-3,"w");if(!i||!o)return 1;for(p=s;;p++)switch(*p++){B'M':
+Q(k=fgetc(i))!=EOF&&k!=*p)*r++=k;if(k==EOF){fputs("}}\n",o);fclose(o);return
+system(q-69);}*r=0 B'P':while(*p!='`')fputc(*p++,o)B'O':Q*r)fputc(*r++,o);p--
+B'C':k=0;Q k<*p-'0')(*r++=fgetc(i),k++);*r=0 B'I':k= *p;if(**R==k)goto G B'G'
+:k= *p;G:p=s;while(*p!='$'||p[1]!= k)p++;p++B'N':R[*p-'0'][0]++;}}}

bugs.md

@@ -652,23 +652,16 @@ If you want to try and fix this (mis)feature, you are welcome to try.
 
 ## 1991 dds
 
-### STATUS: INABIAF - please **DO NOT** fix
+### STATUS: uses gets() - change to fgets() if possible
 ### Source code: [1991/dds/dds.c](1991/dds/dds.c)
 ### Information: [1991/dds/README.md](1991/dds/README.md)
 
-If the BASIC file cannot be opened for reading or the output file cannot be
-opened for writing the program will very likely crash or do something funny.
-This is not a bug but a feature.  Please do not fix this except for the
-challenge to yourself.
-
-### STATUS: uses gets() - change to fgets() if possible
-
-That being said the compiled code uses `gets()` not `fgets()`. Can you fix this?
-It's quite complicated to do: the `s` array is certainly relevant and you can
-see a bit of the magic in the [thanks](/thanks-for-fixes.md) and the README.md
-file for how it works. It's easy enough to get the code to refer to `fgets()`
-and call it correctly but it might take more work to get the generated code
-sorted. This will be looked at later.
+The compiled code uses `gets()` not `fgets()`. Can you fix this?  It's quite
+complicated to do: the `s` array is certainly relevant and you can see a bit of
+the magic in the [thanks](/thanks-for-fixes.md) and the README.md file for how
+it works. It's easy enough to get the code to refer to `fgets()` and call it
+correctly but it might take more work to get the generated code sorted. This
+will be looked at later.
 
 
 ## 1991 westley

thanks-for-fixes.md

@@ -1032,10 +1032,12 @@ slightly more like the original, even though it's unused.
 ## [1991/dds](1991/dds/dds.c) ([README.md](1991/dds/README.md]))
 
 Cody fixed a segfault that prevented this entry from working in any condition
-and he also made it work for clang. Clang (at least in some systems?) defaults
-to having `-Werror` and the code that the entry generates had some warnings
-that were causing compilation to fail as it just ran `cc a.c`. It ran it by what
-was once `system(q-6);` but with clang this was not enough..
+and he also made it work for clang. He also added checks for NULL `FILE *`s.
+
+Clang (at least in some systems?) defaults to having `-Werror` and the code that
+the entry generates had some warnings that were causing compilation to fail as
+it just ran `cc a.c`. It ran it by what was once `system(q-6);` but with clang
+this was not enough.
 
 The following had to be added to the string `s` (which to fix the segfault was
 changed from `char*s` to `char s[]`):