2 files changed, 80 insertions, 6 deletions

diff --git a/gcc/rust/rust-session-manager.cc b/gcc/rust/rust-session-manager.cc
index ec99be7..1a6afd7 100644
--- a/gcc/rust/rust-session-manager.cc
+++ b/gcc/rust/rust-session-manager.cc
@@ -54,7 +54,28 @@ const char *kHIRDumpFile = "gccrs.hir.dump";
 const char *kHIRTypeResolutionDumpFile = "gccrs.type-resolution.dump";
 const char *kTargetOptionsDumpFile = "gccrs.target-options.dump";
 
-const std::string kDefaultCrateName = "example";
+const std::string kDefaultCrateName = "rust_out";
+
+static std::string
+infer_crate_name (const std::string filename)
+{
+  if (filename == "-")
+    return kDefaultCrateName;
+
+  std::string crate = std::string (filename);
+  size_t path_sep = crate.find_last_of (file_separator);
+
+  // find the base filename
+  if (path_sep != std::string::npos)
+    crate.erase (0, path_sep + 1);
+
+  // find the file stem name (remove file extension)
+  size_t ext_position = crate.find_last_of ('.');
+  if (ext_position != std::string::npos)
+    crate.erase (ext_position);
+
+  return crate;
+}
 
 // Implicitly enable a target_feature (and recursively enable dependencies).
 void
@@ -311,10 +332,6 @@ Session::init ()
 
   // setup backend to GCC GIMPLE
   backend = rust_get_backend ();
-
-  // set the default crate name if crate name was unset
-  if (options.crate_name.empty ())
-    options.set_crate_name (kDefaultCrateName);
 }
 
 /* Initialise default options. Actually called before handle_option, unlike init
@@ -479,6 +496,25 @@ Session::enable_dump (std::string arg)
 void
 Session::parse_files (int num_files, const char **files)
 {
+  rust_assert (num_files > 0);
+
+  if (options.crate_name.empty ())
+    {
+      /* HACK: We use the first file to infer the crate name, which might be
+       * incorrect: since rustc only allows one file to be supplied in the
+       * command-line */
+      auto crate_name = infer_crate_name (files[0]);
+      rust_debug_loc (Location (), "inferred crate name: %s",
+		      crate_name.c_str ());
+      if (!options.set_crate_name (crate_name))
+	{
+	  rust_inform (Location (),
+		       "crate name inferred from the input file %<%s%>",
+		       files[0]);
+	  return;
+	}
+    }
+
   auto mappings = Analysis::Mappings::get ();
   CrateNum crate_num = mappings->setup_crate_mappings (options.crate_name);
   mappings->set_current_crate (crate_num);
diff --git a/gcc/rust/rust-session-manager.h b/gcc/rust/rust-session-manager.h
index 8fcc5dd..d4fae27 100644
--- a/gcc/rust/rust-session-manager.h
+++ b/gcc/rust/rust-session-manager.h
@@ -41,6 +41,8 @@ namespace HIR {
 struct Crate;
 }
 
+const size_t kMaxNameLength = 64;
+
 /* Data related to target, most useful for conditional compilation and
  * whatever. */
 struct TargetOptions
@@ -212,9 +214,45 @@ struct CompileOptions
     enable_dump_option (DumpOption::TYPE_RESOLUTION_DUMP);
   }
 
+  /* Validate the crate name using the ASCII rules
+   TODO: Support Unicode version of the rules */
+  bool validate_crate_name (const std::string &crate_name)
+  {
+    if (crate_name.empty ())
+      {
+	rust_error_at (Location (), "crate name cannot be empty");
+	return false;
+      }
+    if (crate_name.length () > kMaxNameLength)
+      {
+	rust_error_at (Location (), "crate name cannot exceed %ld characters",
+		       kMaxNameLength);
+	return false;
+      }
+    for (auto &c : crate_name)
+      {
+	if (!(ISALNUM (c) || c == '_' || c == '-'))
+	  {
+	    rust_error_at (Location (),
+			   "invalid character %<%c%> in crate name: %<%s%>", c,
+			   crate_name.c_str ());
+	    return false;
+	  }
+      }
+    return true;
+  }
+
   bool set_crate_name (std::string name)
   {
-    // TODO: validate the crate name?
+    if (!validate_crate_name (name))
+      return false;
+
+    /* Replace all the '-' symbols with '_' per Rust rules */
+    for (auto &c : name)
+      {
+	if (c == '-')
+	  c = '_';
+      }
     crate_name = std::move (name);
     return true;
   }