curl_setup: Add macros for FOPEN_READTEXT, FOPEN_WRITETEXT

- Change fopen calls to use FOPEN_READTEXT instead of "r" or "rt"
- Change fopen calls to use FOPEN_WRITETEXT instead of "w" or "wt"

This change is to explicitly specify when we need to read/write text.
Unfortunately 't' is not part of POSIX fopen so we can't specify it
directly. Instead we now have FOPEN_READTEXT, FOPEN_WRITETEXT.

Prior to this change we had an issue on Windows if an application that
uses libcurl overrides the default file mode to binary. The default file
mode in Windows is normally text mode (translation mode) and that's what
libcurl expects.

Bug: https://github.com/bagder/curl/pull/258#issuecomment-107093055
Reported-by: Orgad Shaneh

src/tool_cb_dbg.c

@@ -79,7 +79,7 @@ int tool_debug_cb(CURL *handle, curl_infotype type,
       /* Ok, this is somewhat hackish but we do it undocumented for now */
       config->trace_stream = config->errors;  /* aka stderr */
     else {
-      config->trace_stream = fopen(config->trace_dump, "w");
+      config->trace_stream = fopen(config->trace_dump, FOPEN_WRITETEXT);
       config->trace_fopened = TRUE;
     }
   }

src/tool_easysrc.c

@@ -176,7 +176,7 @@ void dumpeasysrc(struct GlobalConfig *config)
     FILE *out;
     bool fopened = FALSE;
     if(strcmp(o, "-")) {
-      out = fopen(o, "w");
+      out = fopen(o, FOPEN_WRITETEXT);
       fopened = TRUE;
     }
     else

src/tool_getparam.c

@@ -681,7 +681,7 @@ ParameterError getparameter(char *flag,    /* f or -long-flag */
 
       case 'v': /* --stderr */
         if(strcmp(nextarg, "-")) {
-          FILE *newfile = fopen(nextarg, "wt");
+          FILE *newfile = fopen(nextarg, FOPEN_WRITETEXT);
           if(!newfile)
             warnf(global, "Failed to open %s!\n", nextarg);
           else {
@@ -1748,7 +1748,7 @@ ParameterError getparameter(char *flag,    /* f or -long-flag */
         }
         else {
           fname = nextarg;
-          file = fopen(nextarg, "r");
+          file = fopen(nextarg, FOPEN_READTEXT);
         }
         err = file2string(&config->writeout, file);
         if(file && (file != stdin))

src/tool_parsecfg.c

@@ -69,7 +69,7 @@ int parseconfig(const char *filename, struct GlobalConfig *global)
         /* Check if the file exists - if not, try CURLRC in the same
          * directory as our executable
          */
-        file = fopen(filebuffer, "r");
+        file = fopen(filebuffer, FOPEN_READTEXT);
         if(file != NULL) {
           fclose(file);
           filename = filebuffer;
@@ -115,7 +115,7 @@ int parseconfig(const char *filename, struct GlobalConfig *global)
   }
 
   if(strcmp(filename, "-"))
-    file = fopen(filename, "r");
+    file = fopen(filename, FOPEN_READTEXT);
   else
     file = stdin;