ffi: use patched cbindgen

I've implemented #[repr(packed)] and #[repr(align(...))] support in cbindgen[1], and the new binary no longer requires the hacks I had to previously apply. [1]: mozilla/cbindgen#431 Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
openSUSE · Dec 15, 2019 · b148ddd · b148ddd
1 parent 3df77c8
commit b148ddd
Show file tree

Hide file tree

Showing 4 changed files with 41 additions and 64 deletions.
diff --git a/cbindgen.toml b/cbindgen.toml
@@ -53,21 +53,6 @@ autogen_warning = """
  */
 """
 
-# Part of workaround for https://github.com/eqrion/cbindgen/issues/430.
-trailer = """
-#ifndef LIBPATHRS_H___CBINDGEN_430_WORKAROUND
-#define LIBPATHRS_H___CBINDGEN_430_WORKAROUND
-/* Part of workaround for https://github.com/eqrion/cbindgen/issues/430. */
-struct pathrs_config_global_t {
-    bool error_backtraces;
-} __attribute__((packed));
-
-struct pathrs_config_root_t {
-    pathrs_resolver_t resolver;
-} __attribute__((packed));
-#endif /* LIBPATHRS_H___CBINDGEN_430_WORKAROUND */
-"""
-
 # Needed for dev_t.
 sys_includes = ["sys/types.h"]
 
@@ -76,6 +61,9 @@ line_length = 80
 tab_width = 4
 style = "type"
 
+[layout]
+packed = "__attribute__((packed))"
+
 [export]
 exclude = [
 	# Useless for C users.
@@ -96,8 +84,6 @@ exclude = [
 include = [
 	"CGlobalConfig",
 	"CRootConfig",
-	# Part of workaround for https://github.com/eqrion/cbindgen/issues/430.
-	"CResolver",
 ]
 
 # Clean up the naming of structs.

diff --git a/contrib/bindings/python/pathrs.py b/contrib/bindings/python/pathrs.py
@@ -339,25 +339,17 @@ def __do_load():
 	# wrote this. :P
 	packed_hdr = ""
 	for struct in packed_structs:
-		patterns = [
-			# struct definition
-			re.compile("^\s*struct\s+%s[\s\n]*{[^}]*}\s*;?" % (struct,), flags=re.MULTILINE),
-			# typedef
-			# TODO: This will absolutely break after we fix the cbindgen
-			#       limitations (this won't handle "typedef struct { ... } foo"
-			#       even remotely correctly).
-			re.compile("^\s*typedef\s+[^;{]*%s[^;{]*;" % (struct,), flags=re.MULTILINE),
-		]
-
-		for pattern in patterns:
-			# Add the matched pattern to the packed header.
-			try:
-				packed_hdr += re.search(pattern, hdr).group() + "\n"
-			except:
-				raise RuntimeError("pathrs.h invalid -- packed-struct=%s listed but struct not defined" % (struct,))
+		# struct definition
+		pattern = re.compile("^typedef\s*struct[^{;]+{[^}]*}\s*%s\s*;?" % (struct,), flags=re.MULTILINE)
+
+		# Add the matched pattern to the packed header.
+		try:
+			packed_hdr += re.search(pattern, hdr).group() + "\n"
+		except:
+			raise RuntimeError("pathrs.h invalid -- packed-struct=%s listed but struct not defined" % (struct,))
 
-			# And drop it from the original header.
-			hdr = re.sub(pattern, "", hdr)
+		# And drop it from the original header.
+		hdr = re.sub(pattern, "", hdr)
 
 	ffi.cdef("typedef uint32_t dev_t;")
 	ffi.cdef(hdr)

diff --git a/include/pathrs.h b/include/pathrs.h
@@ -44,7 +44,7 @@
  * The type of object being passed to "object agnostic" libpathrs functions.
  */
 typedef enum {
-    __INVALID = 0,
+    __PATHRS_INVALID_TYPE = 0,
     /**
      * NULL.
      */
@@ -69,7 +69,7 @@ typedef enum {
  * resolver for a `pathrs_root_t`.
  */
 typedef enum {
-    __INVALID = 0,
+    __PATHRS_INVALID_RESOLVER = 0,
     /**
      * Use the native openat2(2) backend (requires kernel support).
      */
@@ -80,12 +80,6 @@ typedef enum {
     PATHRS_EMULATED_RESOLVER = 61441,
 } pathrs_resolver_t;
 
-/**
- * Global configuration for pathrs, for use with
- *    `pathrs_configure(PATHRS_NONE, NULL)`
- */
-typedef struct pathrs_config_global_t pathrs_config_global_t;
-
 /**
  * This is only exported to work around a Rust compiler restriction. Consider
  * it an implementation detail and don't make use of it.
@@ -98,12 +92,6 @@ typedef struct __pathrs_handle_t __pathrs_handle_t;
  */
 typedef struct __pathrs_root_t __pathrs_root_t;
 
-/**
- * Configuration for a specific `pathrs_root_t`, for use with
- *    `pathrs_configure(PATHRS_ROOT, <root>)`
- */
-typedef struct pathrs_config_root_t pathrs_config_root_t;
-
 /**
  * Represents a single entry in a Rust backtrace in C. This structure is
  * owned by the relevant `pathrs_error_t`.
@@ -204,6 +192,30 @@ typedef __pathrs_handle_t pathrs_handle_t;
  */
 typedef __pathrs_root_t pathrs_root_t;
 
+/**
+ * Global configuration for pathrs, for use with
+ *    `pathrs_configure(PATHRS_NONE, NULL)`
+ */
+typedef struct __attribute__((packed)) {
+    /**
+     * Sets whether backtraces will be generated for errors. This is a global
+     * setting, and defaults to **disabled** for release builds of libpathrs
+     * (but is **enabled** for debug builds).
+     */
+    bool error_backtraces;
+} pathrs_config_global_t;
+
+/**
+ * Configuration for a specific `pathrs_root_t`, for use with
+ *    `pathrs_configure(PATHRS_ROOT, <root>)`
+ */
+typedef struct __attribute__((packed)) {
+    /**
+     * Resolver used for all resolution under this `pathrs_root_t`.
+     */
+    pathrs_resolver_t resolver;
+} pathrs_config_root_t;
+
 /**
  * Configure pathrs and its objects and fetch the current configuration.
  *
@@ -333,16 +345,3 @@ pathrs_handle_t *pathrs_resolve(pathrs_root_t *root, const char *path);
 int pathrs_symlink(pathrs_root_t *root, const char *path, const char *target);
 
 #endif /* LIBPATHRS_H */
-
-#ifndef LIBPATHRS_H___CBINDGEN_430_WORKAROUND
-#define LIBPATHRS_H___CBINDGEN_430_WORKAROUND
-/* Part of workaround for https://github.com/eqrion/cbindgen/issues/430. */
-struct pathrs_config_global_t {
-    bool error_backtraces;
-} __attribute__((packed));
-
-struct pathrs_config_root_t {
-    pathrs_resolver_t resolver;
-} __attribute__((packed));
-#endif /* LIBPATHRS_H___CBINDGEN_430_WORKAROUND */
-
diff --git a/src/ffi/mod.rs b/src/ffi/mod.rs
@@ -522,7 +522,7 @@ trait CConfig {
 #[allow(non_camel_case_types, dead_code)]
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum CResolver {
-    __INVALID = 0,
+    __PATHRS_INVALID_RESOLVER = 0,
     /// Use the native openat2(2) backend (requires kernel support).
     PATHRS_KERNEL_RESOLVER = 0xF000,
     /// Use the userspace "emulated" backend.
@@ -829,7 +829,7 @@ pub extern "C" fn pathrs_configure(
 #[allow(non_camel_case_types, dead_code)]
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum CPointerType {
-    __INVALID = 0,
+    __PATHRS_INVALID_TYPE = 0,
     /// NULL.
     PATHRS_NONE = 0xDFFF,
     /// `pathrs_error_t`