1 files changed, 138 insertions, 0 deletions
diff --git a/src/win32/w32_stack.h b/src/win32/w32_stack.h
new file mode 100644
index 000000000..21170bd2f
--- /dev/null
+++ b/src/win32/w32_stack.h
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#ifndef INCLUDE_w32_stack_h__
+#define INCLUDE_w32_stack_h__
+
+#if defined(GIT_MSVC_CRTDBG)
+
+/**
+ * This type defines a callback to be used to augment a C stacktrace
+ * with "aux" data. This can be used, for example, to allow LibGit2Sharp
+ * (or other interpreted consumer libraries) to give us C# stacktrace
+ * data for the PInvoke.
+ *
+ * This callback will be called during crtdbg-instrumented allocs.
+ *
+ * @param aux_id [out] A returned "aux_id" representing a unique
+ * (de-duped at the C# layer) stacktrace.  "aux_id" 0 is reserved
+ * to mean no aux stacktrace data.
+ */
+typedef void (*git_win32__stack__aux_cb_alloc)(unsigned int *aux_id);
+
+/**
+ * This type defines a callback to be used to augment the output of
+ * a stacktrace.  This will be used to request the C# layer format
+ * the C# stacktrace associated with "aux_id" into the provided
+ * buffer.
+ *
+ * This callback will be called during leak reporting.
+ *
+ * @param aux_id The "aux_id" key associated with a stacktrace.
+ * @param aux_msg A buffer where a formatted message should be written.
+ * @param aux_msg_len The size of the buffer.
+ */
+typedef void (*git_win32__stack__aux_cb_lookup)(unsigned int aux_id, char *aux_msg, unsigned int aux_msg_len);
+
+/**
+ * Register an "aux" data provider to augment our C stacktrace data.
+ *
+ * This can be used, for example, to allow LibGit2Sharp (or other
+ * interpreted consumer libraries) to give us the C# stacktrace of
+ * the PInvoke.
+ *
+ * If you choose to use this feature, it should be registered during
+ * initialization and not changed for the duration of the process.
+ */
+GIT_EXTERN(int) git_win32__stack__set_aux_cb(
+	git_win32__stack__aux_cb_alloc cb_alloc,
+	git_win32__stack__aux_cb_lookup cb_lookup);
+
+/**
+ * Maximum number of stackframes to record for a
+ * single stacktrace.
+ */
+#define GIT_WIN32__STACK__MAX_FRAMES 30
+
+/**
+ * Wrapper containing the raw unprocessed stackframe
+ * data for a single stacktrace and any "aux_id".
+ *
+ * I put the aux_id first so leaks will be sorted by it.
+ * So, for example, if a specific callstack in C# leaks
+ * a repo handle, all of the pointers within the associated
+ * repo pointer will be grouped together.
+ */
+typedef struct {
+	unsigned int aux_id;
+	unsigned int nr_frames;
+	void *frames[GIT_WIN32__STACK__MAX_FRAMES];
+} git_win32__stack__raw_data;
+
+
+/**
+ * Load symbol table data.  This should be done in the primary
+ * thread at startup (under a lock if there are other threads
+ * active).
+ */
+void git_win32__stack_init(void);
+
+/**
+ * Cleanup symbol table data.  This should be done in the
+ * primary thead at shutdown (under a lock if there are other
+ * threads active).
+ */
+void git_win32__stack_cleanup(void);
+
+
+/**
+ * Capture raw stack trace data for the current process/thread.
+ *
+ * @param skip Number of initial frames to skip.  Pass 0 to
+ * begin with the caller of this routine. Pass 1 to begin
+ * with its caller.  And so on.
+ */
+int git_win32__stack_capture(git_win32__stack__raw_data *pdata, int skip);
+
+/**
+ * Compare 2 raw stacktraces with the usual -1,0,+1 result.
+ * This includes any "aux_id" values in the comparison, so that
+ * our de-dup is also "aux" context relative.
+ */
+int git_win32__stack_compare(
+	git_win32__stack__raw_data *d1,
+	git_win32__stack__raw_data *d2);
+
+/**
+ * Format raw stacktrace data into buffer WITHOUT using any mallocs.
+ *
+ * @param prefix String written before each frame; defaults to "\t".
+ * @param suffix String written after each frame; defaults to "\n".
+ */
+int git_win32__stack_format(
+	char *pbuf, int buf_len,
+	const git_win32__stack__raw_data *pdata,
+	const char *prefix, const char *suffix);
+
+/**
+ * Convenience routine to capture and format stacktrace into
+ * a buffer WITHOUT using any mallocs.  This is primarily a
+ * wrapper for testing.
+ *
+ * @param skip Number of initial frames to skip. Pass 0 to
+ * begin with the caller of this routine.  Pass 1 to begin
+ * with its caller.  And so on.
+ * @param prefix String written before each frame; defaults to "\t".
+ * @param suffix String written after each frame; defaults to "\n".
+ */
+int git_win32__stack(
+	char * pbuf, int buf_len,
+	int skip,
+	const char *prefix, const char *suffix);
+
+#endif /* GIT_MSVC_CRTDBG */
+#endif /* INCLUDE_w32_stack_h__ */