[project @ 2003-03-18 14:36:56 by simonmar]

Fix a profiling crash on Windows.

fprint_ccs used snprintf() to avoid overflowing a buffer; on mingw32
where snprintf() doesn't exist we were just using the straight
sprintf(), which inevitably lead to a crash.  Rewritten to use a
homegrown non-overflowing string copying function - it actually looks
nicer now, anwyay.

diff --git a/ghc/rts/ProfHeap.c b/ghc/rts/ProfHeap.c
index 51fa3df..fea4abc 100644 (file)
--- a/ghc/rts/ProfHeap.c
+++ b/ghc/rts/ProfHeap.c
@@ -1,7 +1,7 @@
 /* -----------------------------------------------------------------------------
- * $Id: ProfHeap.c,v 1.43 2003/02/20 15:39:59 simonmar Exp $
+ * $Id: ProfHeap.c,v 1.44 2003/03/18 14:36:56 simonmar Exp $
  *
- * (c) The GHC Team, 1998-2000
+ * (c) The GHC Team, 1998-2003
  *
  * Support for heap profiling
  *
@@ -479,13 +479,24 @@ endHeapProfiling(void)
 
 
 #ifdef PROFILING
+static size_t
+buf_append(char *p, const char *q, char *end)
+{
+    int m;
+
+    for (m = 0; p < end; p++, q++, m++) {
+       *p = *q;
+       if (*q == '\0') { break; }
+    }
+    return m;
+}
+
 static void
 fprint_ccs(FILE *fp, CostCentreStack *ccs, nat max_length)
 {
-    char buf[max_length+1];
+    char buf[max_length+1], *p, *buf_end;
     nat next_offset = 0;
     nat written;
-    char *template;
 
     // MAIN on its own gets printed as "MAIN", otherwise we ignore MAIN.
     if (ccs == CCS_MAIN) {
@@ -495,6 +506,9 @@ fprint_ccs(FILE *fp, CostCentreStack *ccs, nat max_length)
 
     fprintf(fp, "(%d)", ccs->ccsID);
 
+    p = buf;
+    buf_end = buf + max_length + 1;
+
     // keep printing components of the stack until we run out of space
     // in the buffer.  If we run out of space, end with "...".
     for (; ccs != NULL && ccs != CCS_MAIN; ccs = ccs->prevStack) {
@@ -502,31 +516,16 @@ fprint_ccs(FILE *fp, CostCentreStack *ccs, nat max_length)
        // CAF cost centres print as M.CAF, but we leave the module
        // name out of all the others to save space.
        if (!strcmp(ccs->cc->label,"CAF")) {
-#ifdef HAVE_SNPRINTF
-           written = snprintf(buf+next_offset, 
-                              (int)max_length-3-(int)next_offset,
-                              "%s.CAF", ccs->cc->module);
-#else
-           written = sprintf(buf+next_offset, 
-                              "%s.CAF", ccs->cc->module);
-#endif
+           p += buf_append(p, ccs->cc->module, buf_end);
+           p += buf_append(p, ".CAF", buf_end);
        } else {
            if (ccs->prevStack != NULL && ccs->prevStack != CCS_MAIN) {
-               template = "%s/";
-           } else {
-               template = "%s";
+               p += buf_append(p, "/", buf_end);
            }
-#ifdef HAVE_SNPRINTF
-           written = snprintf(buf+next_offset, 
-                              (int)max_length-3-(int)next_offset,
-                              template, ccs->cc->label);
-#else
-           written = sprintf(buf+next_offset, 
-                              template, ccs->cc->label);
-#endif
+           p += buf_append(p, ccs->cc->label, buf_end);
        }
-
-       if (next_offset+written >= max_length-4) {
+       
+       if (p >= buf_end) {
            sprintf(buf+max_length-4, "...");
            break;
        } else {