library_exported_names_each_alias(), library_exported_names_each() now restartable

These function now takes a *start_after, and return a pointer to the first
failing key, like the other ltrace iterators

4 files changed, 52 insertions, 40 deletions

diff --git a/library.c b/library.c
index 3754af1..aa23262 100644
--- a/library.c
+++ b/library.c
@@ -445,31 +445,28 @@ struct library_exported_names_each_context
 {
 	enum callback_status (*inner_cb)(const char *, void *);
 	void *data;
-	bool failure : 1;
 };
 static enum callback_status
 library_exported_names_each_cb(const char **key, uint64_t *value, void *data)
 {
 	struct library_exported_names_each_context *context =
 		(struct library_exported_names_each_context*)data;
-	enum callback_status status = context->inner_cb(*key, context->data);
-	if (status == CBS_FAIL)
-		context->failure = true;
-	return status;
+	return context->inner_cb(*key, context->data);
 }
-bool library_exported_names_each(const struct library_exported_names *names,
-				 enum callback_status (*cb)(const char *,
-							    void *),
-				 void *data)
+const char** library_exported_names_each(
+	const struct library_exported_names *names,
+	const char **name_start_after,
+	enum callback_status (*cb)(const char *,
+				   void *),
+	void *data)
 {
 	struct library_exported_names_each_context context =
 		{.inner_cb = cb,
-		 .data = data,
-		 .failure = false};
-	DICT_EACH(&names->names,
-		  const char*, uint64_t,
-		  NULL, library_exported_names_each_cb, &context);
-	return !context.failure;
+		 .data = data};
+	return DICT_EACH(&names->names,
+			 const char*, uint64_t,
+			 name_start_after, library_exported_names_each_cb,
+			 &context);
 }
 
 struct library_exported_names_each_alias_context
@@ -477,7 +474,6 @@ struct library_exported_names_each_alias_context
 	enum callback_status (*inner_cb)(const char *, void *);
 	const char *origname;
 	void *data;
-	bool failure : 1;
 };
 static enum callback_status
 library_exported_names_each_alias_cb(const char **name, void *data)
@@ -491,15 +487,13 @@ library_exported_names_each_alias_cb(const char **name, void *data)
 	if (strcmp(*name, context->origname) == 0)
 		return CBS_CONT;
 
-	enum callback_status status = context->inner_cb(*name, context->data);
-	if (status == CBS_FAIL)
-		context->failure = true;
-	return status;
+	return context->inner_cb(*name, context->data);
 }
 
-bool library_exported_names_each_alias(
+const char** library_exported_names_each_alias(
 	const struct library_exported_names *names,
 	const char *aliasname,
+	const char **name_start_after,
 	enum callback_status (*cb)(const char *,
 				   void *),
 	void *data)
@@ -509,22 +503,19 @@ bool library_exported_names_each_alias(
 	uint64_t *addr = DICT_FIND_REF(&names->names,
 				       &aliasname, uint64_t);
 	if (addr == NULL)
-		return false;
+		return NULL;
 
 	// OK. I have an address. Get the list of symbols at this address
 	struct vect **aliases = DICT_FIND_REF(&names->addrs,
-					     addr, struct vect*);
-	if (aliases == NULL)
-		return false;
+					      addr, struct vect*);
+	assert(aliases != NULL);
 
 	struct library_exported_names_each_alias_context context =
 		{.inner_cb = cb,
 		 .origname = aliasname,
-		 .data = data,
-		 .failure = false};
-	VECT_EACH(*aliases, const char*, NULL,
-		  library_exported_names_each_alias_cb, &context);
-	return true;
+		 .data = data};
+	return VECT_EACH(*aliases, const char*, name_start_after,
+			 library_exported_names_each_alias_cb, &context);
 }
 
 
diff --git a/library.h b/library.h
index f8a5cf8..71ac4db 100644
--- a/library.h
+++ b/library.h
@@ -265,22 +265,42 @@ int library_exported_names_push(struct library_exported_names *names,
 
 /* Iterates through the a library's export list. The callback is called for
  * every symbol a library exports. Symbol aliases do not apply here. If multiple
- * symbols are defined at the same address, each is reported here. Returns true
- * on success. If the callback fails at any point, this returns false
+ * symbols are defined at the same address, each is reported here.
+ *
+ * If we want to iterate through the whole list, set name_start_after=NULL. If
+ * we want to start iterating immediately past a particular symbol name, pass a
+ * pointer to this symbol name in name_start_after. This must be a pointer in
+ * the internal dict, preferably returned by an earlier call to this function
+ *
+ * If the callback fails at any point, a pointer to the failing key is returned.
+ * On success, returns NULL. The returned pointer can be passed back to this
+ * function in name_start_after to resume skipping this element
  */
-bool library_exported_names_each(const struct library_exported_names *names,
-				 enum callback_status (*cb)(const char *,
-							    void *),
-				 void *data);
+const char** library_exported_names_each(
+	const struct library_exported_names *names,
+	const char **name_start_after,
+	enum callback_status (*cb)(const char *,
+				   void *),
+	void *data);
 
 /* Iterates through the a library's export list, reporting each symbol that is
  * an alias of the given 'aliasname' symbol. This 'aliasname' symbol itself is
  * NOT reported, so if this symbol is unique, the callback is not called at all.
- * Returns true on success
+ *
+ * If we want to iterate through the whole alias list, set
+ * name_start_after=NULL. If we want to start iterating immediately past a
+ * particular symbol name, pass a pointer to this symbol name in
+ * name_start_after. This must be a pointer in the internal dict, preferably
+ * returned by an earlier call to this function
+ *
+ * If the callback fails at any point, a pointer to the failing key is returned.
+ * On success, returns NULL. The returned pointer can be passed back to this
+ * function in name_start_after to resume skipping this element
  */
-bool library_exported_names_each_alias(
+const char** library_exported_names_each_alias(
 	const struct library_exported_names *names,
 	const char *aliasname,
+	const char **name_start_after,
 	enum callback_status (*cb)(const char *,
 				   void *),
 	void *data);
diff --git a/output.c b/output.c
index 2128816..b63befe 100644
--- a/output.c
+++ b/output.c
@@ -267,7 +267,7 @@ library_get_prototype(struct library *lib, const char *name)
 	struct lookup_prototype_alias_context context = {.lib = lib,
 							 .result = NULL};
 	library_exported_names_each_alias(&lib->exported_names, name,
-					  lookup_prototype_alias_cb,
+					  NULL, lookup_prototype_alias_cb,
 					  &context);
 
 	// if found, the prototype is stored here, otherwise it's NULL
diff --git a/proc.c b/proc.c
index 6d6562f..394dad0 100644
--- a/proc.c
+++ b/proc.c
@@ -903,8 +903,9 @@ activate_latent_in(struct process *proc, struct library *lib, void *data)
 	struct activate_latent_in_context context = {.proc = proc,
 						     .lib = lib};
 	if (library_exported_names_each(exported_names,
+					NULL,
 					activate_latent_in_cb,
-					&context))
+					&context) == NULL)
 		return CBS_CONT;
 	else
 		return CBS_FAIL;