Add a command-line program to tool/ that will check source code files for

the presence of tabs, carriage-returns, whitespace at the ends of lines,
and blank lines at the ends of files.

FossilOrigin-Name: 656a9c8b47d262e0982ad3a35db490e2ff4d856e

tool/checkSpacing.c

@@ -0,0 +1,67 @@
+/*
+** This program checks for formatting problems in source code:
+**
+**    *  Any use of tab characters
+**    *  White space at the end of a line
+**    *  Blank lines at the end of a file
+**
+** Any violations are reported.
+*/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static void checkSpacing(const char *zFile, int crok){
+  FILE *in = fopen(zFile, "rb");
+  int i;
+  int seenSpace;
+  int seenTab;
+  int ln = 0;
+  int lastNonspace = 0;
+  char zLine[2000];
+  if( in==0 ){
+    printf("cannot open %s\n", zFile);
+    return;
+  }
+  while( fgets(zLine, sizeof(zLine), in) ){
+    seenSpace = 0;
+    seenTab = 0;
+    ln++;
+    for(i=0; zLine[i]; i++){
+      if( zLine[i]=='\t' && seenTab==0 ){
+        printf("%s:%d: tab (\\t) character\n", zFile, ln);
+        seenTab = 1;
+      }else if( zLine[i]=='\r' ){
+        if( !crok ){
+          printf("%s:%d: carriage-return (\\r) character\n", zFile, ln);
+        }
+      }else if( zLine[i]==' ' ){
+        seenSpace = 1;
+      }else if( zLine[i]!='\n' ){
+        lastNonspace = ln;
+        seenSpace = 0;
+      }
+    }
+    if( seenSpace ){
+      printf("%s:%d: whitespace at end-of-line\n", zFile, ln);
+    }
+  }
+  fclose(in);
+  if( lastNonspace<ln ){
+    printf("%s:%d: blank lines at end of file (%d)\n",
+        zFile, ln, ln - lastNonspace);
+  }
+}
+
+int main(int argc, char **argv){
+  int i;
+  int crok = 0;
+  for(i=1; i<argc; i++){
+    if( strcmp(argv[i], "--crok")==0 ){
+      crok = 1;
+    }else{
+      checkSpacing(argv[i], crok);
+    }
+  }
+  return 0;
+}