tool_urlglob: Allow a glob range with the same start and stop

For example allow ranges like [1-1] and [a-a] etc.

Regression since 5ca96cb.

Bug: https://github.com/curl/curl/issues/1238
Reported-by: R. Dennis Steed

src/tool_urlglob.c

@@ -189,7 +189,7 @@ static CURLcode glob_range(URLGlob *glob, char **patternp,
     char min_c;
     char max_c;
     char end_c;
-    int step=1;
+    unsigned long step = 1;
 
     pat->type = UPTCharRange;
 
@@ -198,17 +198,12 @@ static CURLcode glob_range(URLGlob *glob, char **patternp,
     if(rc == 3) {
       if(end_c == ':') {
         char *endp;
-        unsigned long lstep;
         errno = 0;
-        lstep = strtoul(&pattern[4], &endp, 10);
+        step = strtoul(&pattern[4], &endp, 10);
         if(errno || &pattern[4] == endp || *endp != ']')
-          step = -1;
-        else {
+          step = 0;
+        else
           pattern = endp+1;
-          step = (int)lstep;
-          if(step > (max_c - min_c))
-            step = -1;
-        }
       }
       else if(end_c != ']')
         /* then this is wrong */
@@ -220,19 +215,21 @@ static CURLcode glob_range(URLGlob *glob, char **patternp,
 
     *posp += (pattern - *patternp);
 
-    if((rc != 3) || (min_c >= max_c) || ((max_c - min_c) > ('z' - 'a')) ||
-       (step <= 0) )
+    if(rc != 3 || !step || step > (unsigned)INT_MAX ||
+       (min_c == max_c && step != 1) ||
+       (min_c != max_c && (min_c > max_c || step > (unsigned)(max_c - min_c) ||
+                           (max_c - min_c) > ('z' - 'a'))))
       /* the pattern is not well-formed */
       return GLOBERROR("bad range", *posp, CURLE_URL_MALFORMAT);
 
     /* if there was a ":[num]" thing, use that as step or else use 1 */
-    pat->content.CharRange.step = step;
+    pat->content.CharRange.step = (int)step;
     pat->content.CharRange.ptr_c = pat->content.CharRange.min_c = min_c;
     pat->content.CharRange.max_c = max_c;
 
-    if(multiply(amount, (pat->content.CharRange.max_c -
+    if(multiply(amount, ((pat->content.CharRange.max_c -
                           pat->content.CharRange.min_c) /
-                         pat->content.CharRange.step + 1) )
+                         pat->content.CharRange.step + 1)))
       return GLOBERROR("range overflow", *posp, CURLE_URL_MALFORMAT);
   }
   else if(ISDIGIT(*pattern)) {
@@ -293,7 +290,9 @@ static CURLcode glob_range(URLGlob *glob, char **patternp,
     fail:
     *posp += (pattern - *patternp);
 
-    if(!endp || (min_n > max_n) || (step_n > (max_n - min_n)) || !step_n)
+    if(!endp || !step_n ||
+       (min_n == max_n && step_n != 1) ||
+       (min_n != max_n && (min_n > max_n || step_n > (max_n - min_n))))
       /* the pattern is not well-formed */
       return GLOBERROR("bad range", *posp, CURLE_URL_MALFORMAT);
 
@@ -303,9 +302,9 @@ static CURLcode glob_range(URLGlob *glob, char **patternp,
     pat->content.NumRange.max_n = max_n;
     pat->content.NumRange.step = step_n;
 
-    if(multiply(amount, (pat->content.NumRange.max_n -
-                         pat->content.NumRange.min_n) /
-                        pat->content.NumRange.step + 1) )
+    if(multiply(amount, ((pat->content.NumRange.max_n -
+                          pat->content.NumRange.min_n) /
+                         pat->content.NumRange.step + 1)))
       return GLOBERROR("range overflow", *posp, CURLE_URL_MALFORMAT);
   }
   else

tests/data/Makefile.inc

@@ -130,7 +130,7 @@ test1236 test1237 test1238 test1239 test1240 test1241 test1242 test1243 \
 test1244 test1245 test1246 test1247 test1248 test1249 test1250 test1251 \
 test1252 test1253 test1254 test1255 test1256 test1257 test1258 test1259 \
 \
-test1280 test1281 test1282 \
+test1280 test1281 test1282 test1283 \
 \
 test1300 test1301 test1302 test1303 test1304 test1305 test1306 test1307 \
 test1308 test1309 test1310 test1311 test1312 test1313 test1314 test1315 \

tests/data/test1283

@@ -0,0 +1,57 @@
+<testcase>
+<info>
+<keywords>
+HTTP
+HTTP GET
+globbing
+[] range
+</keywords>
+</info>
+
+#
+# Server-side
+<reply>
+<data nocheck="yes">
+HTTP/1.1 200 OK
+Date: Thu, 09 Nov 2010 14:49:00 GMT
+Content-Length: 6
+Connection: close
+
+bytes
+</data>
+</reply>
+
+# Client-side
+<client>
+<server>
+http
+</server>
+<name>
+globbing range with same start and stop
+</name>
+<command option="no-output">
+http://%HOSTIP:%HTTPPORT/[a-a][1-1][b-b:1][2-2:1]/1283 -o "log/outfile1283_#1#2#3#4.dump"
+</command>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+<strip>
+^User-Agent:.*
+</strip>
+<protocol>
+GET /a1b2/1283 HTTP/1.1
+Host: %HOSTIP:%HTTPPORT
+Accept: */*
+
+</protocol>
+<file name="log/outfile1283_a1b2.dump">
+HTTP/1.1 200 OK
+Date: Thu, 09 Nov 2010 14:49:00 GMT
+Content-Length: 6
+Connection: close
+
+bytes
+</file>
+</verify>
+</testcase>