dwarflint: Improve error messages in check_read_[us]leb128

diff --git a/src/dwarflint.c b/src/dwarflint.c
index d335b38899f3a1f075a32d8b8121d8c4ae711c24..6c910c51db6c95f46a13f3133aaafa7bdb9f8af7 100644 (file)
--- a/src/dwarflint.c
+++ b/src/dwarflint.c
@@ -195,16 +195,18 @@ wr_format_padding_message (enum message_category category,
 }
 
 void
-wr_format_leb128_message (int st, struct where *wh, const char *what)
+wr_format_leb128_message (struct where *where, const char *what,
+                         const char *purpose,
+                         const unsigned char *begin, const unsigned char *end)
 {
   enum message_category category = mc_leb128 | mc_acc_bloat | mc_impact_3;
-  if (st == 0)
-    return;
-
-  if (st < 0)
-    wr_error (wh, ": can't read %s.\n", what);
-  else if (st > 0)
-    wr_message (category, wh, ": unnecessarily long encoding of %s.\n", what);
+  char buf[(end - begin) * 3 + 1]; // 2 hexa digits+" " per byte, and term. 0
+  char *ptr = buf;
+  for (; begin < end; ++begin)
+    ptr += sprintf (ptr, " %02x", *begin);
+  wr_message (category, where,
+             ": %s: value %s encoded as `%s'.\n",
+             what, purpose, buf + 1);
 }
 
 void
@@ -1144,10 +1146,18 @@ read_ctx_read_uleb128 (struct read_ctx *ctx, uint64_t *ret)
 
 static bool
 checked_read_uleb128 (struct read_ctx *ctx, uint64_t *ret,
-                     struct where *wh, const char *what)
+                     struct where *where, const char *what)
 {
+  const unsigned char *ptr = ctx->ptr;
   int st = read_ctx_read_uleb128 (ctx, ret);
-  wr_format_leb128_message (st, wh, what);
+  if (st < 0)
+    wr_error (where, ": can't read %s.\n", what);
+  else if (st > 0)
+    {
+      char buf[19]; // 16 hexa digits, "0x", terminating zero
+      sprintf (buf, "%#" PRIx64, *ret);
+      wr_format_leb128_message (where, what, buf, ptr, ctx->ptr);
+    }
   return st >= 0;
 }
 
@@ -1189,10 +1199,19 @@ read_ctx_read_sleb128 (struct read_ctx *ctx, int64_t *ret)
 
 static bool
 checked_read_sleb128 (struct read_ctx *ctx, int64_t *ret,
-                        struct where *wh, const char *what)
+                     struct where *where, const char *what)
 {
+  const unsigned char *ptr = ctx->ptr;
   int st = read_ctx_read_sleb128 (ctx, ret);
-  wr_format_leb128_message (st, wh, what);
+  if (st < 0)
+    wr_error (where, ": can't read %s.\n", what);
+  else if (st > 0)
+    {
+      char buf[20]; // sign, "0x", 16 hexa digits, terminating zero
+      int64_t val = *ret;
+      sprintf (buf, "%s%#" PRIx64, val < 0 ? "-" : "", val < 0 ? -val : val);
+      wr_format_leb128_message (where, what, buf, ptr, ctx->ptr);
+    }
   return st >= 0;
 }
 

diff --git a/src/dwarflint.h b/src/dwarflint.h
index eede53e3f0a55fb89a9c53b51531c2ec81ae72ac..335226755a61aaa181642f65c47756d2bd5f1284 100644 (file)
--- a/src/dwarflint.h
+++ b/src/dwarflint.h
@@ -129,8 +129,10 @@ extern "C"
                                         uint64_t start, uint64_t end,
                                         char *kind);
 
-  extern void wr_format_leb128_message (int st, struct where *wh,
-                                       const char *what);
+  extern void wr_format_leb128_message (struct where *where, const char *what,
+                                       const char *purpose,
+                                       const unsigned char *begin,
+                                       const unsigned char *end);
 
   extern void wr_message_padding_0 (enum message_category category,
                                    struct where *wh,