parseconfig: dash options can't specified with colon or equals

Bug: http://curl.haxx.se/bug/view.cgi?id=1297
Reported-by: Michael Osipov

docs/curl.1

@@ -722,16 +722,21 @@ See this online resource for further details:
 .IP "-K, --config <config file>"
 Specify which config file to read curl arguments from. The config file is a
 text file in which command line arguments can be written which then will be
-used as if they were written on the actual command line. Options and their
-parameters must be specified on the same config file line, separated by
-whitespace, colon, the equals sign or any combination thereof (however,
-the preferred separator is the equals sign). If the parameter is to contain
-whitespace, the parameter must be enclosed within quotes. Within double
-quotes, the following escape sequences are available: \\\\, \\", \\t, \\n,
-\\r and \\v. A backslash preceding any other letter is ignored. If the
-first column of a config line is a '#' character, the rest of the line will be
-treated as a comment. Only write one option per physical line in the config
-file.
+used as if they were written on the actual command line.
+
+Options and their parameters must be specified on the same config file line,
+separated by whitespace, colon, or the equals sign. Long option names can
+optionally be given in the config file without the initial double dashes and
+if so, the colon or equals characters can be used as separators. If the option
+is specified with one or two dashes, there can be no colon or equals character
+between the option and its parameter.
+
+If the parameter is to contain whitespace, the parameter must be enclosed
+within quotes. Within double quotes, the following escape sequences are
+available: \\\\, \\", \\t, \\n, \\r and \\v. A backslash preceding any other
+letter is ignored. If the first column of a config line is a '#' character,
+the rest of the line will be treated as a comment. Only write one option per
+physical line in the config file.
 
 Specify the filename to -K, --config as '-' to make curl read the file from
 stdin.
@@ -742,9 +747,6 @@ line. So, it could look similar to this:
 
 url = "http://curl.haxx.se/docs/"
 
-Long option names can optionally be given in the config file without the
-initial double dashes.
-
 When curl is invoked, it always (unless \fI-q\fP is used) checks for a default
 config file and uses it if found. The default config file is checked for in
 the following places in this order:

src/tool_parsecfg.c

@@ -35,7 +35,10 @@
 #include "memdebug.h" /* keep this as LAST include */
 
 #define CURLRC DOT_CHAR "curlrc"
-#define ISSEP(x) (((x) == '=') || ((x) == ':'))
+
+/* only acknowledge colon or equals as separators if the option was not
+   specified with an initial dash! */
+#define ISSEP(x,dash) (!dash && (((x) == '=') || ((x) == ':')))
 
 static const char *unslashquote(const char *line, char *param);
 static char *my_get_line(FILE *fp);
@@ -123,6 +126,7 @@ int parseconfig(const char *filename,
     char *param;
     int lineno = 0;
     bool alloced_param;
+    bool dashed_option;
 
     while(NULL != (aline = my_get_line(file))) {
       lineno++;
@@ -146,7 +150,11 @@ int parseconfig(const char *filename,
 
       /* the option keywords starts here */
       option = line;
-      while(*line && !ISSPACE(*line) && !ISSEP(*line))
+
+      /* the option starts with a dash? */
+      dashed_option = option[0]=='-'?TRUE:FALSE;
+
+      while(*line && !ISSPACE(*line) && !ISSEP(*line, dashed_option))
         line++;
       /* ... and has ended here */
 
@@ -158,7 +166,7 @@ int parseconfig(const char *filename,
 #endif
 
       /* pass spaces and separator(s) */
-      while(*line && (ISSPACE(*line) || ISSEP(*line)))
+      while(*line && (ISSPACE(*line) || ISSEP(*line, dashed_option)))
         line++;
 
       /* the parameter starts here (unless quoted) */