[libclang] Introduce libclang APIs for creating a buffer with a JSON virtual file overlay description.

The current API only supports adding 'virtual file path' -> 'real file path' mappings.

rdar://15986708

llvm-svn: 202105

3 files changed, 109 insertions, 38 deletions

diff --git a/clang/include/clang-c/BuildSystem.h b/clang/include/clang-c/BuildSystem.h
index f8eff4257df..ab581fdcced 100644
--- a/clang/include/clang-c/BuildSystem.h
+++ b/clang/include/clang-c/BuildSystem.h
@@ -15,6 +15,7 @@
 #define CLANG_C_BUILD_SYSTEM_H
 
 #include "clang-c/Platform.h"
+#include "clang-c/CXErrorCode.h"
 #include "clang-c/CXString.h"
 
 #ifdef __cplusplus
@@ -33,6 +34,48 @@ extern "C" {
 CINDEX_LINKAGE unsigned long long clang_getBuildSessionTimestamp(void);
 
 /**
+ * \brief Object encapsulating information about overlaying virtual
+ * file/directories over the real file system.
+ */
+typedef struct CXVirtualFileOverlayImpl *CXVirtualFileOverlay;
+
+/**
+ * \brief Create a \c CXVirtualFileOverlay object.
+ * Must be disposed with \c clang_VirtualFileOverlay_dispose().
+ *
+ * \param options is reserved, always pass 0.
+ */
+CINDEX_LINKAGE CXVirtualFileOverlay
+clang_VirtualFileOverlay_create(unsigned options);
+
+/**
+ * \brief Map an absolute virtual file path to an absolute real one.
+ * The virtual path must be canonicalized (not contain "."/"..").
+ * \returns 0 for success, non-zero to indicate an error.
+ */
+CINDEX_LINKAGE enum CXErrorCode
+clang_VirtualFileOverlay_addFileMapping(CXVirtualFileOverlay,
+                                        const char *virtualPath,
+                                        const char *realPath);
+
+/**
+ * \brief Write out the \c CXVirtualFileOverlay object to a char buffer.
+ *
+ * \param options is reserved, always pass 0.
+ * \param out_buffer pointer to receive the CXString object, which should be
+ * disposed using \c clang_disposeString().
+ * \returns 0 for success, non-zero to indicate an error.
+ */
+CINDEX_LINKAGE enum CXErrorCode
+clang_VirtualFileOverlay_writeToBuffer(CXVirtualFileOverlay, unsigned options,
+                                       CXString *out_buffer);
+
+/**
+ * \brief Dispose a \c CXVirtualFileOverlay object.
+ */
+CINDEX_LINKAGE void clang_VirtualFileOverlay_dispose(CXVirtualFileOverlay);
+
+/**
  * @}
  */
 
diff --git a/clang/include/clang-c/CXErrorCode.h b/clang/include/clang-c/CXErrorCode.h
new file mode 100644
index 00000000000..a026c95a5bb
--- /dev/null
+++ b/clang/include/clang-c/CXErrorCode.h
@@ -0,0 +1,64 @@
+/*===-- clang-c/CXErrorCode.h - C Index Error Codes  --------------*- C -*-===*\
+|*                                                                            *|
+|*                     The LLVM Compiler Infrastructure                       *|
+|*                                                                            *|
+|* This file is distributed under the University of Illinois Open Source      *|
+|* License. See LICENSE.TXT for details.                                      *|
+|*                                                                            *|
+|*===----------------------------------------------------------------------===*|
+|*                                                                            *|
+|* This header provides the CXErrorCode enumerators.                          *|
+|*                                                                            *|
+\*===----------------------------------------------------------------------===*/
+
+#ifndef CLANG_C_CXERRORCODE_H
+#define CLANG_C_CXERRORCODE_H
+
+#include "clang-c/Platform.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief Error codes returned by libclang routines.
+ *
+ * Zero (\c CXError_Success) is the only error code indicating success.  Other
+ * error codes, including not yet assigned non-zero values, indicate errors.
+ */
+enum CXErrorCode {
+  /**
+   * \brief No error.
+   */
+  CXError_Success = 0,
+
+  /**
+   * \brief A generic error code, no further details are available.
+   *
+   * Errors of this kind can get their own specific error codes in future
+   * libclang versions.
+   */
+  CXError_Failure = 1,
+
+  /**
+   * \brief libclang crashed while performing the requested operation.
+   */
+  CXError_Crashed = 2,
+
+  /**
+   * \brief The function detected that the arguments violate the function
+   * contract.
+   */
+  CXError_InvalidArguments = 3,
+
+  /**
+   * \brief An AST deserialization error has occurred.
+   */
+  CXError_ASTReadError = 4
+};
+
+#ifdef __cplusplus
+}
+#endif
+#endif
+
diff --git a/clang/include/clang-c/Index.h b/clang/include/clang-c/Index.h
index eece5fb9756..9c37ac745bb 100644
--- a/clang/include/clang-c/Index.h
+++ b/clang/include/clang-c/Index.h
@@ -19,6 +19,7 @@
 #include <time.h>
 
 #include "clang-c/Platform.h"
+#include "clang-c/CXErrorCode.h"
 #include "clang-c/CXString.h"
 #include "clang-c/BuildSystem.h"
 
@@ -31,7 +32,7 @@
  * compatible, thus CINDEX_VERSION_MAJOR is expected to remain stable.
  */
 #define CINDEX_VERSION_MAJOR 0
-#define CINDEX_VERSION_MINOR 23
+#define CINDEX_VERSION_MINOR 24
 
 #define CINDEX_VERSION_ENCODE(major, minor) ( \
       ((major) * 10000)                       \
@@ -74,43 +75,6 @@ extern "C" {
  */
 
 /**
- * \brief Error codes returned by libclang routines.
- *
- * Zero (\c CXError_Success) is the only error code indicating success.  Other
- * error codes, including not yet assigned non-zero values, indicate errors.
- */
-enum CXErrorCode {
-  /**
-   * \brief No error.
-   */
-  CXError_Success = 0,
-
-  /**
-   * \brief A generic error code, no further details are available.
-   *
-   * Errors of this kind can get their own specific error codes in future
-   * libclang versions.
-   */
-  CXError_Failure = 1,
-
-  /**
-   * \brief libclang crashed while performing the requested operation.
-   */
-  CXError_Crashed = 2,
-
-  /**
-   * \brief The function detected that the arguments violate the function
-   * contract.
-   */
-  CXError_InvalidArguments = 3,
-
-  /**
-   * \brief An AST deserialization error has occurred.
-   */
-  CXError_ASTReadError = 4
-};
-
-/**
  * \brief An "index" that consists of a set of translation units that would
  * typically be linked together into an executable or library.
  */