win32: "crtdbg" is now "leakcheck"

msvc crtdbg is a mouthfull that is not particularly indicative of what
it does.  Let's rename it to "win32 leakcheck".

8 files changed, 476 insertions, 498 deletions

diff --git a/src/alloc.c b/src/alloc.c
index 6972e7b59..eedf85aa7 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -12,8 +12,7 @@
 #include "allocators/win32_crtdbg.h"
 
 #if defined(GIT_MSVC_CRTDBG)
-# include "win32/w32_stack.h"
-# include "win32/w32_crtdbg_stacktrace.h"
+# include "win32/w32_leakcheck.h"
 #endif
 
 git_allocator git__allocator;
@@ -30,16 +29,16 @@ static int setup_default_allocator(void)
 #if defined(GIT_MSVC_CRTDBG)
 static void allocator_global_shutdown(void)
 {
-	git_win32__crtdbg_stacktrace_cleanup();
-	git_win32__stack_cleanup();
+	git_win32_leakcheck_stacktrace_cleanup();
+	git_win32_leakcheck_stack_cleanup();
 }
 #endif
 
 int git_allocator_global_init(void)
 {
 #if defined(GIT_MSVC_CRTDBG)
-	git_win32__crtdbg_stacktrace_init();
-	git_win32__stack_init();
+	git_win32_leakcheck_stacktrace_init();
+	git_win32_leakcheck_stack_init();
 
 	if (git_runtime_shutdown_register(allocator_global_shutdown) < 0)
 		return -1;
diff --git a/src/allocators/win32_crtdbg.c b/src/allocators/win32_crtdbg.c
index c726268a8..c542b0c54 100644
--- a/src/allocators/win32_crtdbg.c
+++ b/src/allocators/win32_crtdbg.c
@@ -9,26 +9,25 @@
 
 #if defined(GIT_MSVC_CRTDBG)
 
-#include "win32/w32_stack.h"
-#include "win32/w32_crtdbg_stacktrace.h"
+#include "win32/w32_leakcheck.h"
 
 static void *crtdbg__malloc(size_t len, const char *file, int line)
 {
-	void *ptr = _malloc_dbg(len, _NORMAL_BLOCK, git_win32__crtdbg_stacktrace(1,file), line);
+	void *ptr = _malloc_dbg(len, _NORMAL_BLOCK, git_win32_leakcheck_stacktrace(1,file), line);
 	if (!ptr) git_error_set_oom();
 	return ptr;
 }
 
 static void *crtdbg__calloc(size_t nelem, size_t elsize, const char *file, int line)
 {
-	void *ptr = _calloc_dbg(nelem, elsize, _NORMAL_BLOCK, git_win32__crtdbg_stacktrace(1,file), line);
+	void *ptr = _calloc_dbg(nelem, elsize, _NORMAL_BLOCK, git_win32_leakcheck_stacktrace(1,file), line);
 	if (!ptr) git_error_set_oom();
 	return ptr;
 }
 
 static char *crtdbg__strdup(const char *str, const char *file, int line)
 {
-	char *ptr = _strdup_dbg(str, _NORMAL_BLOCK, git_win32__crtdbg_stacktrace(1,file), line);
+	char *ptr = _strdup_dbg(str, _NORMAL_BLOCK, git_win32_leakcheck_stacktrace(1,file), line);
 	if (!ptr) git_error_set_oom();
 	return ptr;
 }
@@ -68,7 +67,7 @@ static char *crtdbg__substrdup(const char *start, size_t n, const char *file, in
 
 static void *crtdbg__realloc(void *ptr, size_t size, const char *file, int line)
 {
-	void *new_ptr = _realloc_dbg(ptr, size, _NORMAL_BLOCK, git_win32__crtdbg_stacktrace(1,file), line);
+	void *new_ptr = _realloc_dbg(ptr, size, _NORMAL_BLOCK, git_win32_leakcheck_stacktrace(1,file), line);
 	if (!new_ptr) git_error_set_oom();
 	return new_ptr;
 }
diff --git a/src/libgit2.c b/src/libgit2.c
index 316d89365..2e9cb8510 100644
--- a/src/libgit2.c
+++ b/src/libgit2.c
@@ -31,7 +31,6 @@
 #include "transports/smart.h"
 #include "transports/http.h"
 #include "transports/ssh.h"
-#include "win32/w32_stack.h"
 
 #ifdef GIT_OPENSSL
 # include <openssl/err.h>
diff --git a/src/win32/w32_crtdbg_stacktrace.h b/src/win32/w32_crtdbg_stacktrace.h
deleted file mode 100644
index d65154bab..000000000
--- a/src/win32/w32_crtdbg_stacktrace.h
+++ /dev/null
@@ -1,127 +0,0 @@
-/*
- * 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_win32_w32_crtdbg_stacktrace_h__
-#define INCLUDE_win32_w32_crtdbg_stacktrace_h__
-
-#include "common.h"
-
-#if defined(GIT_MSVC_CRTDBG)
-
-#include <stdlib.h>
-#include <crtdbg.h>
-
-#include "git2/errors.h"
-#include "strnlen.h"
-
-/* MSVC CRTDBG memory leak reporting.
- *
- * We DO NOT use the "_CRTDBG_MAP_ALLOC" macro described in the MSVC
- * documentation because all allocs/frees in libgit2 already go through
- * the "git__" routines defined in this file.  Simply using the normal
- * reporting mechanism causes all leaks to be attributed to a routine
- * here in util.h (ie, the actual call to calloc()) rather than the
- * caller of git__calloc().
- *
- * Therefore, we declare a set of "git__crtdbg__" routines to replace
- * the corresponding "git__" routines and re-define the "git__" symbols
- * as macros.  This allows us to get and report the file:line info of
- * the real caller.
- *
- * We DO NOT replace the "git__free" routine because it needs to remain
- * a function pointer because it is used as a function argument when
- * setting up various structure "destructors".
- *
- * We also DO NOT use the "_CRTDBG_MAP_ALLOC" macro because it causes
- * "free" to be remapped to "_free_dbg" and this causes problems for
- * structures which define a field named "free".
- *
- * Finally, CRTDBG must be explicitly enabled and configured at program
- * startup.  See tests/main.c for an example.
- */
-
-/**
- * Initialize our memory leak tracking and de-dup data structures.
- * This should ONLY be called by git_libgit2_init().
- */
-void git_win32__crtdbg_stacktrace_init(void);
-
-/**
- * Shutdown our memory leak tracking and dump summary data.
- * This should ONLY be called by git_libgit2_shutdown().
- *
- * We explicitly call _CrtDumpMemoryLeaks() during here so
- * that we can compute summary data for the leaks. We print
- * the stacktrace of each unique leak.
- *
- * This cleanup does not happen if the app calls exit()
- * without calling the libgit2 shutdown code.
- *
- * This info we print here is independent of any automatic
- * reporting during exit() caused by _CRTDBG_LEAK_CHECK_DF.
- * Set it in your app if you also want traditional reporting.
- */
-void git_win32__crtdbg_stacktrace_cleanup(void);
-
-/**
- * Checkpoint options.
- */
-typedef enum git_win32__crtdbg_stacktrace_options {
-	/**
-	 * Set checkpoint marker.
-	 */
-	GIT_WIN32__CRTDBG_STACKTRACE__SET_MARK         = (1 << 0),
-
-	/**
-	 * Dump leaks since last checkpoint marker.
-	 * May not be combined with __LEAKS_TOTAL.
-	 *
-	 * Note that this may generate false positives for global TLS
-	 * error state and other global caches that aren't cleaned up
-	 * until the thread/process terminates.  So when using this
-	 * around a region of interest, also check the final (at exit)
-	 * dump before digging into leaks reported here.
-	 */
-	GIT_WIN32__CRTDBG_STACKTRACE__LEAKS_SINCE_MARK = (1 << 1),
-
-	/**
-	 * Dump leaks since init.  May not be combined
-	 * with __LEAKS_SINCE_MARK.
-	 */
-	GIT_WIN32__CRTDBG_STACKTRACE__LEAKS_TOTAL      = (1 << 2),
-
-	/**
-	 * Suppress printing during dumps.
-	 * Just return leak count.
-	 */
-	GIT_WIN32__CRTDBG_STACKTRACE__QUIET            = (1 << 3),
-
-} git_win32__crtdbg_stacktrace_options;
-
-/**
- * Checkpoint memory state and/or dump unique stack traces of
- * current memory leaks.
- *
- * @return number of unique leaks (relative to requested starting
- * point) or error.
- */
-GIT_EXTERN(int) git_win32__crtdbg_stacktrace__dump(
-	git_win32__crtdbg_stacktrace_options opt,
-	const char *label);
-
-/**
- * Construct stacktrace and append it to the global buffer.
- * Return pointer to start of this string.  On any error or
- * lack of buffer space, just return the given file buffer
- * so it will behave as usual.
- *
- * This should ONLY be called by our internal memory allocations
- * routines.
- */
-const char *git_win32__crtdbg_stacktrace(int skip, const char *file);
-
-#endif
-#endif
diff --git a/src/win32/w32_crtdbg_stacktrace.c b/src/win32/w32_leakcheck.c
index 22a353d58..4fc3ec489 100644
--- a/src/win32/w32_crtdbg_stacktrace.c
+++ b/src/win32/w32_leakcheck.c
@@ -5,12 +5,192 @@
  * a Linking Exception. For full terms see the included COPYING file.
  */
 
-#include "w32_crtdbg_stacktrace.h"
+#include "w32_leakcheck.h"
 
 #if defined(GIT_MSVC_CRTDBG)
-#include "w32_stack.h"
 
-#define CRTDBG_STACKTRACE__UID_LEN (15)
+#include "Windows.h"
+#include "Dbghelp.h"
+#include "win32/posix.h"
+#include "hash.h"
+
+/* Stack frames (for stack tracing, below) */
+
+static bool   g_win32_stack_initialized = false;
+static HANDLE g_win32_stack_process = INVALID_HANDLE_VALUE;
+static git_win32_leakcheck_stack_aux_cb_alloc  g_aux_cb_alloc  = NULL;
+static git_win32_leakcheck_stack_aux_cb_lookup g_aux_cb_lookup = NULL;
+
+int git_win32_leakcheck_stack_set_aux_cb(
+	git_win32_leakcheck_stack_aux_cb_alloc cb_alloc,
+	git_win32_leakcheck_stack_aux_cb_lookup cb_lookup)
+{
+	g_aux_cb_alloc = cb_alloc;
+	g_aux_cb_lookup = cb_lookup;
+
+	return 0;
+}
+
+void git_win32_leakcheck_stack_init(void)
+{
+	if (!g_win32_stack_initialized) {
+		g_win32_stack_process = GetCurrentProcess();
+		SymSetOptions(SYMOPT_LOAD_LINES);
+		SymInitialize(g_win32_stack_process, NULL, TRUE);
+		g_win32_stack_initialized = true;
+	}
+}
+
+void git_win32_leakcheck_stack_cleanup(void)
+{
+	if (g_win32_stack_initialized) {
+		SymCleanup(g_win32_stack_process);
+		g_win32_stack_process = INVALID_HANDLE_VALUE;
+		g_win32_stack_initialized = false;
+	}
+}
+
+int git_win32_leakcheck_stack_capture(git_win32_leakcheck_stack_raw_data *pdata, int skip)
+{
+	if (!g_win32_stack_initialized) {
+		git_error_set(GIT_ERROR_INVALID, "git_win32_stack not initialized.");
+		return GIT_ERROR;
+	}
+
+	memset(pdata, 0, sizeof(*pdata));
+	pdata->nr_frames = RtlCaptureStackBackTrace(
+		skip+1, GIT_WIN32_LEAKCHECK_STACK_MAX_FRAMES, pdata->frames, NULL);
+
+	/* If an "aux" data provider was registered, ask it to capture
+	 * whatever data it needs and give us an "aux_id" to it so that
+	 * we can refer to it later when reporting.
+	 */
+	if (g_aux_cb_alloc)
+		(g_aux_cb_alloc)(&pdata->aux_id);
+
+	return 0;
+}
+
+int git_win32_leakcheck_stack_compare(
+	git_win32_leakcheck_stack_raw_data *d1,
+	git_win32_leakcheck_stack_raw_data *d2)
+{
+	return memcmp(d1, d2, sizeof(*d1));
+}
+
+int git_win32_leakcheck_stack_format(
+	char *pbuf, size_t buf_len,
+	const git_win32_leakcheck_stack_raw_data *pdata,
+	const char *prefix, const char *suffix)
+{
+#define MY_MAX_FILENAME 255
+
+	/* SYMBOL_INFO has char FileName[1] at the end.  The docs say to
+	 * to malloc it with extra space for your desired max filename.
+	 */
+	struct {
+		SYMBOL_INFO symbol;
+		char extra[MY_MAX_FILENAME + 1];
+	} s;
+
+	IMAGEHLP_LINE64 line;
+	size_t buf_used = 0;
+	unsigned int k;
+	char detail[MY_MAX_FILENAME * 2]; /* filename plus space for function name and formatting */
+	size_t detail_len;
+
+	if (!g_win32_stack_initialized) {
+		git_error_set(GIT_ERROR_INVALID, "git_win32_stack not initialized.");
+		return GIT_ERROR;
+	}
+
+	if (!prefix)
+		prefix = "\t";
+	if (!suffix)
+		suffix = "\n";
+
+	memset(pbuf, 0, buf_len);
+
+	memset(&s, 0, sizeof(s));
+	s.symbol.MaxNameLen = MY_MAX_FILENAME;
+	s.symbol.SizeOfStruct = sizeof(SYMBOL_INFO);
+
+	memset(&line, 0, sizeof(line));
+	line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
+
+	for (k=0; k < pdata->nr_frames; k++) {
+		DWORD64 frame_k = (DWORD64)pdata->frames[k];
+		DWORD dwUnused;
+
+		if (SymFromAddr(g_win32_stack_process, frame_k, 0, &s.symbol) &&
+			SymGetLineFromAddr64(g_win32_stack_process, frame_k, &dwUnused, &line)) {
+			const char *pslash;
+			const char *pfile;
+
+			pslash = strrchr(line.FileName, '\\');
+			pfile = ((pslash) ? (pslash+1) : line.FileName);
+			p_snprintf(detail, sizeof(detail), "%s%s:%d> %s%s",
+					   prefix, pfile, line.LineNumber, s.symbol.Name, suffix);
+		} else {
+			/* This happens when we cross into another module.
+			 * For example, in CLAR tests, this is typically
+			 * the CRT startup code.  Just print an unknown
+			 * frame and continue.
+			 */
+			p_snprintf(detail, sizeof(detail), "%s??%s", prefix, suffix);
+		}
+		detail_len = strlen(detail);
+
+		if (buf_len < (buf_used + detail_len + 1)) {
+			/* we don't have room for this frame in the buffer, so just stop. */
+			break;
+		}
+
+		memcpy(&pbuf[buf_used], detail, detail_len);
+		buf_used += detail_len;
+	}
+
+	/* "aux_id" 0 is reserved to mean no aux data. This is needed to handle
+	 * allocs that occur before the aux callbacks were registered.
+	 */
+	if (pdata->aux_id > 0) {
+		p_snprintf(detail, sizeof(detail), "%saux_id: %d%s",
+				   prefix, pdata->aux_id, suffix);
+		detail_len = strlen(detail);
+		if ((buf_used + detail_len + 1) < buf_len) {
+			memcpy(&pbuf[buf_used], detail, detail_len);
+			buf_used += detail_len;
+		}
+
+		/* If an "aux" data provider is still registered, ask it to append its detailed
+		 * data to the end of ours using the "aux_id" it gave us when this de-duped
+		 * item was created.
+		 */
+		if (g_aux_cb_lookup)
+			(g_aux_cb_lookup)(pdata->aux_id, &pbuf[buf_used], (buf_len - buf_used - 1));
+	}
+
+	return GIT_OK;
+}
+
+int git_win32_leakcheck_stack(
+	char * pbuf, size_t buf_len,
+	int skip,
+	const char *prefix, const char *suffix)
+{
+	git_win32_leakcheck_stack_raw_data data;
+	int error;
+
+	if ((error = git_win32_leakcheck_stack_capture(&data, skip)) < 0)
+		return error;
+	if ((error = git_win32_leakcheck_stack_format(pbuf, buf_len, &data, prefix, suffix)) < 0)
+		return error;
+	return 0;
+}
+
+/* Strack tracing */
+
+#define STACKTRACE_UID_LEN (15)
 
 /**
  * The stacktrace of an allocation can be distilled
@@ -20,20 +200,20 @@
  * give to the CRT malloc routines.
  */
 typedef struct {
-	char uid[CRTDBG_STACKTRACE__UID_LEN + 1];
-} git_win32__crtdbg_stacktrace__uid;
+	char uid[STACKTRACE_UID_LEN + 1];
+} git_win32_leakcheck_stacktrace_uid;
 
 /**
  * All mallocs with the same stacktrace will be de-duped
  * and aggregated into this row.
  */
 typedef struct {
-	git_win32__crtdbg_stacktrace__uid uid; /* must be first */
-	git_win32__stack__raw_data raw_data;
+	git_win32_leakcheck_stacktrace_uid uid; /* must be first */
+	git_win32_leakcheck_stack_raw_data raw_data;
 	unsigned int count_allocs; /* times this alloc signature seen since init */
 	unsigned int count_allocs_at_last_checkpoint; /* times since last mark */
 	unsigned int transient_count_leaks; /* sum of leaks */
-} git_win32__crtdbg_stacktrace__row;
+} git_win32_leakcheck_stacktrace_row;
 
 static CRITICAL_SECTION g_crtdbg_stacktrace_cs;
 
@@ -58,8 +238,8 @@ static CRITICAL_SECTION g_crtdbg_stacktrace_cs;
  */
 
 #define MY_ROW_LIMIT (2 * 1024 * 1024)
-static git_win32__crtdbg_stacktrace__row  g_cs_rows[MY_ROW_LIMIT];
-static git_win32__crtdbg_stacktrace__row *g_cs_index[MY_ROW_LIMIT];
+static git_win32_leakcheck_stacktrace_row  g_cs_rows[MY_ROW_LIMIT];
+static git_win32_leakcheck_stacktrace_row *g_cs_index[MY_ROW_LIMIT];
 
 static unsigned int g_cs_end = MY_ROW_LIMIT;
 static unsigned int g_cs_ins = 0; /* insertion point == unique allocs seen */
@@ -76,18 +256,18 @@ static bool g_transient_leaks_since_mark = false; /* payload for hook */
  */
 static int row_cmp(const void *v1, const void *v2)
 {
-	git_win32__stack__raw_data *d1 = (git_win32__stack__raw_data*)v1;
-	git_win32__crtdbg_stacktrace__row *r2 = (git_win32__crtdbg_stacktrace__row *)v2;
+	git_win32_leakcheck_stack_raw_data *d1 = (git_win32_leakcheck_stack_raw_data*)v1;
+	git_win32_leakcheck_stacktrace_row *r2 = (git_win32_leakcheck_stacktrace_row *)v2;
 
-	return (git_win32__stack_compare(d1, &r2->raw_data));
+	return (git_win32_leakcheck_stack_compare(d1, &r2->raw_data));
 }
 
 /**
  * Unique insert the new data into the row and index tables.
  * We have to sort by the stackframe data itself, not the uid.
  */
-static git_win32__crtdbg_stacktrace__row * insert_unique(
-	const git_win32__stack__raw_data *pdata)
+static git_win32_leakcheck_stacktrace_row * insert_unique(
+	const git_win32_leakcheck_stack_raw_data *pdata)
 {
 	size_t pos;
 	if (git__bsearch(g_cs_index, g_cs_ins, pdata, row_cmp, &pos) < 0) {
@@ -206,7 +386,7 @@ static void dump_summary(const char *label)
 					g_cs_rows[k].count_allocs);
 			my_output(buf);
 
-			if (git_win32__stack_format(
+			if (git_win32_leakcheck_stack_format(
 					buf, sizeof(buf), &g_cs_rows[k].raw_data,
 					NULL, NULL) >= 0) {
 				my_output(buf);
@@ -219,7 +399,7 @@ static void dump_summary(const char *label)
 	fflush(stderr);
 }
 
-void git_win32__crtdbg_stacktrace_init(void)
+void git_win32_leakcheck_stacktrace_init(void)
 {
 	InitializeCriticalSection(&g_crtdbg_stacktrace_cs);
 
@@ -238,8 +418,8 @@ void git_win32__crtdbg_stacktrace_init(void)
 	LeaveCriticalSection(&g_crtdbg_stacktrace_cs);
 }
 
-int git_win32__crtdbg_stacktrace__dump(
-	git_win32__crtdbg_stacktrace_options opt,
+int git_win32_leakcheck_stacktrace_dump(
+	git_win32_leakcheck_stacktrace_options opt,
 	const char *label)
 {
 	_CRT_REPORT_HOOK old;
@@ -248,10 +428,10 @@ int git_win32__crtdbg_stacktrace__dump(
 
 #define IS_BIT_SET(o,b) (((o) & (b)) != 0)
 
-	bool b_set_mark         = IS_BIT_SET(opt, GIT_WIN32__CRTDBG_STACKTRACE__SET_MARK);
-	bool b_leaks_since_mark = IS_BIT_SET(opt, GIT_WIN32__CRTDBG_STACKTRACE__LEAKS_SINCE_MARK);
-	bool b_leaks_total      = IS_BIT_SET(opt, GIT_WIN32__CRTDBG_STACKTRACE__LEAKS_TOTAL);
-	bool b_quiet            = IS_BIT_SET(opt, GIT_WIN32__CRTDBG_STACKTRACE__QUIET);
+	bool b_set_mark         = IS_BIT_SET(opt, GIT_WIN32_LEAKCHECK_STACKTRACE_SET_MARK);
+	bool b_leaks_since_mark = IS_BIT_SET(opt, GIT_WIN32_LEAKCHECK_STACKTRACE_LEAKS_SINCE_MARK);
+	bool b_leaks_total      = IS_BIT_SET(opt, GIT_WIN32_LEAKCHECK_STACKTRACE_LEAKS_TOTAL);
+	bool b_quiet            = IS_BIT_SET(opt, GIT_WIN32_LEAKCHECK_STACKTRACE_QUIET);
 
 	if (b_leaks_since_mark && b_leaks_total) {
 		git_error_set(GIT_ERROR_INVALID, "cannot combine LEAKS_SINCE_MARK and LEAKS_TOTAL.");
@@ -301,7 +481,7 @@ int git_win32__crtdbg_stacktrace__dump(
 	return r;
 }
 
-void git_win32__crtdbg_stacktrace_cleanup(void)
+void git_win32_leakcheck_stacktrace_cleanup(void)
 {
 	/* At shutdown/cleanup, dump cummulative leak info
 	 * with everything since startup.  This might generate
@@ -310,20 +490,20 @@ void git_win32__crtdbg_stacktrace_cleanup(void)
 	 * positives for resources previously reported during
 	 * checkpoints.
 	 */
-	git_win32__crtdbg_stacktrace__dump(
-		GIT_WIN32__CRTDBG_STACKTRACE__LEAKS_TOTAL,
+	git_win32_leakcheck_stacktrace_dump(
+		GIT_WIN32_LEAKCHECK_STACKTRACE_LEAKS_TOTAL,
 		"CLEANUP");
 
 	DeleteCriticalSection(&g_crtdbg_stacktrace_cs);
 }
 
-const char *git_win32__crtdbg_stacktrace(int skip, const char *file)
+const char *git_win32_leakcheck_stacktrace(int skip, const char *file)
 {
-	git_win32__stack__raw_data new_data;
-	git_win32__crtdbg_stacktrace__row *row;
+	git_win32_leakcheck_stack_raw_data new_data;
+	git_win32_leakcheck_stacktrace_row *row;
 	const char * result = file;
 
-	if (git_win32__stack_capture(&new_data, skip+1) < 0)
+	if (git_win32_leakcheck_stack_capture(&new_data, skip+1) < 0)
 		return result;
 
 	EnterCriticalSection(&g_crtdbg_stacktrace_cs);
diff --git a/src/win32/w32_leakcheck.h b/src/win32/w32_leakcheck.h
new file mode 100644
index 000000000..518f5ad7d
--- /dev/null
+++ b/src/win32/w32_leakcheck.h
@@ -0,0 +1,256 @@
+/*
+ * 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_win32_leakcheck_h__
+#define INCLUDE_win32_leakcheck_h__
+
+#include "common.h"
+
+#if defined(GIT_MSVC_CRTDBG)
+
+#include <stdlib.h>
+#include <crtdbg.h>
+
+#include "git2/errors.h"
+#include "strnlen.h"
+
+/* Stack frames (for stack tracing, below) */
+
+/**
+ * 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_leakcheck_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_leakcheck_stack_aux_cb_lookup)(unsigned int aux_id, char *aux_msg, size_t 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.
+ */
+int git_win32_leakcheck_stack_set_aux_cb(
+	git_win32_leakcheck_stack_aux_cb_alloc cb_alloc,
+	git_win32_leakcheck_stack_aux_cb_lookup cb_lookup);
+
+/**
+ * Maximum number of stackframes to record for a
+ * single stacktrace.
+ */
+#define GIT_WIN32_LEAKCHECK_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_LEAKCHECK_STACK_MAX_FRAMES];
+} git_win32_leakcheck_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_leakcheck_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_leakcheck_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_leakcheck_stack_capture(git_win32_leakcheck_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_leakcheck_stack_compare(
+	git_win32_leakcheck_stack_raw_data *d1,
+	git_win32_leakcheck_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_leakcheck_stack_format(
+	char *pbuf, size_t buf_len,
+	const git_win32_leakcheck_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_leakcheck_stack(
+	char * pbuf, size_t buf_len,
+	int skip,
+	const char *prefix, const char *suffix);
+
+/* Stack tracing */
+
+/* MSVC CRTDBG memory leak reporting.
+ *
+ * We DO NOT use the "_CRTDBG_MAP_ALLOC" macro described in the MSVC
+ * documentation because all allocs/frees in libgit2 already go through
+ * the "git__" routines defined in this file.  Simply using the normal
+ * reporting mechanism causes all leaks to be attributed to a routine
+ * here in util.h (ie, the actual call to calloc()) rather than the
+ * caller of git__calloc().
+ *
+ * Therefore, we declare a set of "git__crtdbg__" routines to replace
+ * the corresponding "git__" routines and re-define the "git__" symbols
+ * as macros.  This allows us to get and report the file:line info of
+ * the real caller.
+ *
+ * We DO NOT replace the "git__free" routine because it needs to remain
+ * a function pointer because it is used as a function argument when
+ * setting up various structure "destructors".
+ *
+ * We also DO NOT use the "_CRTDBG_MAP_ALLOC" macro because it causes
+ * "free" to be remapped to "_free_dbg" and this causes problems for
+ * structures which define a field named "free".
+ *
+ * Finally, CRTDBG must be explicitly enabled and configured at program
+ * startup.  See tests/main.c for an example.
+ */
+
+/**
+ * Initialize our memory leak tracking and de-dup data structures.
+ * This should ONLY be called by git_libgit2_init().
+ */
+void git_win32_leakcheck_stacktrace_init(void);
+
+/**
+ * Shutdown our memory leak tracking and dump summary data.
+ * This should ONLY be called by git_libgit2_shutdown().
+ *
+ * We explicitly call _CrtDumpMemoryLeaks() during here so
+ * that we can compute summary data for the leaks. We print
+ * the stacktrace of each unique leak.
+ *
+ * This cleanup does not happen if the app calls exit()
+ * without calling the libgit2 shutdown code.
+ *
+ * This info we print here is independent of any automatic
+ * reporting during exit() caused by _CRTDBG_LEAK_CHECK_DF.
+ * Set it in your app if you also want traditional reporting.
+ */
+void git_win32_leakcheck_stacktrace_cleanup(void);
+
+/**
+ * Checkpoint options.
+ */
+typedef enum git_win32_leakcheck_stacktrace_options {
+	/**
+	 * Set checkpoint marker.
+	 */
+	GIT_WIN32_LEAKCHECK_STACKTRACE_SET_MARK         = (1 << 0),
+
+	/**
+	 * Dump leaks since last checkpoint marker.
+	 * May not be combined with _LEAKS_TOTAL.
+	 *
+	 * Note that this may generate false positives for global TLS
+	 * error state and other global caches that aren't cleaned up
+	 * until the thread/process terminates.  So when using this
+	 * around a region of interest, also check the final (at exit)
+	 * dump before digging into leaks reported here.
+	 */
+	GIT_WIN32_LEAKCHECK_STACKTRACE_LEAKS_SINCE_MARK = (1 << 1),
+
+	/**
+	 * Dump leaks since init.  May not be combined
+	 * with _LEAKS_SINCE_MARK.
+	 */
+	GIT_WIN32_LEAKCHECK_STACKTRACE_LEAKS_TOTAL      = (1 << 2),
+
+	/**
+	 * Suppress printing during dumps.
+	 * Just return leak count.
+	 */
+	GIT_WIN32_LEAKCHECK_STACKTRACE_QUIET            = (1 << 3),
+
+} git_win32_leakcheck_stacktrace_options;
+
+/**
+ * Checkpoint memory state and/or dump unique stack traces of
+ * current memory leaks.
+ *
+ * @return number of unique leaks (relative to requested starting
+ * point) or error.
+ */
+int git_win32_leakcheck_stacktrace_dump(
+	git_win32_leakcheck_stacktrace_options opt,
+	const char *label);
+
+/**
+ * Construct stacktrace and append it to the global buffer.
+ * Return pointer to start of this string.  On any error or
+ * lack of buffer space, just return the given file buffer
+ * so it will behave as usual.
+ *
+ * This should ONLY be called by our internal memory allocations
+ * routines.
+ */
+const char *git_win32_leakcheck_stacktrace(int skip, const char *file);
+
+#endif
+#endif
diff --git a/src/win32/w32_stack.c b/src/win32/w32_stack.c
deleted file mode 100644
index 78c78dbbd..000000000
--- a/src/win32/w32_stack.c
+++ /dev/null
@@ -1,188 +0,0 @@
-/*
- * 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.
- */
-
-#include "w32_stack.h"
-
-#if defined(GIT_MSVC_CRTDBG)
-#include "Windows.h"
-#include "Dbghelp.h"
-#include "win32/posix.h"
-#include "hash.h"
-
-static bool   g_win32_stack_initialized = false;
-static HANDLE g_win32_stack_process = INVALID_HANDLE_VALUE;
-static git_win32__stack__aux_cb_alloc  g_aux_cb_alloc  = NULL;
-static git_win32__stack__aux_cb_lookup g_aux_cb_lookup = NULL;
-
-int git_win32__stack__set_aux_cb(
-	git_win32__stack__aux_cb_alloc cb_alloc,
-	git_win32__stack__aux_cb_lookup cb_lookup)
-{
-	g_aux_cb_alloc = cb_alloc;
-	g_aux_cb_lookup = cb_lookup;
-
-	return 0;
-}
-
-void git_win32__stack_init(void)
-{
-	if (!g_win32_stack_initialized) {
-		g_win32_stack_process = GetCurrentProcess();
-		SymSetOptions(SYMOPT_LOAD_LINES);
-		SymInitialize(g_win32_stack_process, NULL, TRUE);
-		g_win32_stack_initialized = true;
-	}
-}
-
-void git_win32__stack_cleanup(void)
-{
-	if (g_win32_stack_initialized) {
-		SymCleanup(g_win32_stack_process);
-		g_win32_stack_process = INVALID_HANDLE_VALUE;
-		g_win32_stack_initialized = false;
-	}
-}
-
-int git_win32__stack_capture(git_win32__stack__raw_data *pdata, int skip)
-{
-	if (!g_win32_stack_initialized) {
-		git_error_set(GIT_ERROR_INVALID, "git_win32_stack not initialized.");
-		return GIT_ERROR;
-	}
-
-	memset(pdata, 0, sizeof(*pdata));
-	pdata->nr_frames = RtlCaptureStackBackTrace(
-		skip+1, GIT_WIN32__STACK__MAX_FRAMES, pdata->frames, NULL);
-
-	/* If an "aux" data provider was registered, ask it to capture
-	 * whatever data it needs and give us an "aux_id" to it so that
-	 * we can refer to it later when reporting.
-	 */
-	if (g_aux_cb_alloc)
-		(g_aux_cb_alloc)(&pdata->aux_id);
-
-	return 0;
-}
-
-int git_win32__stack_compare(
-	git_win32__stack__raw_data *d1,
-	git_win32__stack__raw_data *d2)
-{
-	return memcmp(d1, d2, sizeof(*d1));
-}
-
-int git_win32__stack_format(
-	char *pbuf, size_t buf_len,
-	const git_win32__stack__raw_data *pdata,
-	const char *prefix, const char *suffix)
-{
-#define MY_MAX_FILENAME 255
-
-	/* SYMBOL_INFO has char FileName[1] at the end.  The docs say to
-	 * to malloc it with extra space for your desired max filename.
-	 */
-	struct {
-		SYMBOL_INFO symbol;
-		char extra[MY_MAX_FILENAME + 1];
-	} s;
-
-	IMAGEHLP_LINE64 line;
-	size_t buf_used = 0;
-	unsigned int k;
-	char detail[MY_MAX_FILENAME * 2]; /* filename plus space for function name and formatting */
-	size_t detail_len;
-
-	if (!g_win32_stack_initialized) {
-		git_error_set(GIT_ERROR_INVALID, "git_win32_stack not initialized.");
-		return GIT_ERROR;
-	}
-
-	if (!prefix)
-		prefix = "\t";
-	if (!suffix)
-		suffix = "\n";
-
-	memset(pbuf, 0, buf_len);
-
-	memset(&s, 0, sizeof(s));
-	s.symbol.MaxNameLen = MY_MAX_FILENAME;
-	s.symbol.SizeOfStruct = sizeof(SYMBOL_INFO);
-
-	memset(&line, 0, sizeof(line));
-	line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
-
-	for (k=0; k < pdata->nr_frames; k++) {
-		DWORD64 frame_k = (DWORD64)pdata->frames[k];
-		DWORD dwUnused;
-
-		if (SymFromAddr(g_win32_stack_process, frame_k, 0, &s.symbol) &&
-			SymGetLineFromAddr64(g_win32_stack_process, frame_k, &dwUnused, &line)) {
-			const char *pslash;
-			const char *pfile;
-
-			pslash = strrchr(line.FileName, '\\');
-			pfile = ((pslash) ? (pslash+1) : line.FileName);
-			p_snprintf(detail, sizeof(detail), "%s%s:%d> %s%s",
-					   prefix, pfile, line.LineNumber, s.symbol.Name, suffix);
-		} else {
-			/* This happens when we cross into another module.
-			 * For example, in CLAR tests, this is typically
-			 * the CRT startup code.  Just print an unknown
-			 * frame and continue.
-			 */
-			p_snprintf(detail, sizeof(detail), "%s??%s", prefix, suffix);
-		}
-		detail_len = strlen(detail);
-
-		if (buf_len < (buf_used + detail_len + 1)) {
-			/* we don't have room for this frame in the buffer, so just stop. */
-			break;
-		}
-
-		memcpy(&pbuf[buf_used], detail, detail_len);
-		buf_used += detail_len;
-	}
-
-	/* "aux_id" 0 is reserved to mean no aux data. This is needed to handle
-	 * allocs that occur before the aux callbacks were registered.
-	 */
-	if (pdata->aux_id > 0) {
-		p_snprintf(detail, sizeof(detail), "%saux_id: %d%s",
-				   prefix, pdata->aux_id, suffix);
-		detail_len = strlen(detail);
-		if ((buf_used + detail_len + 1) < buf_len) {
-			memcpy(&pbuf[buf_used], detail, detail_len);
-			buf_used += detail_len;
-		}
-
-		/* If an "aux" data provider is still registered, ask it to append its detailed
-		 * data to the end of ours using the "aux_id" it gave us when this de-duped
-		 * item was created.
-		 */
-		if (g_aux_cb_lookup)
-			(g_aux_cb_lookup)(pdata->aux_id, &pbuf[buf_used], (buf_len - buf_used - 1));
-	}
-
-	return GIT_OK;
-}
-
-int git_win32__stack(
-	char * pbuf, size_t buf_len,
-	int skip,
-	const char *prefix, const char *suffix)
-{
-	git_win32__stack__raw_data data;
-	int error;
-
-	if ((error = git_win32__stack_capture(&data, skip)) < 0)
-		return error;
-	if ((error = git_win32__stack_format(pbuf, buf_len, &data, prefix, suffix)) < 0)
-		return error;
-	return 0;
-}
-
-#endif
diff --git a/src/win32/w32_stack.h b/src/win32/w32_stack.h
deleted file mode 100644
index c2565c228..000000000
--- a/src/win32/w32_stack.h
+++ /dev/null
@@ -1,140 +0,0 @@
-/*
- * 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_win32_w32_stack_h__
-#define INCLUDE_win32_w32_stack_h__
-
-#include "common.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, size_t 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, size_t 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, size_t buf_len,
-	int skip,
-	const char *prefix, const char *suffix);
-
-#endif /* GIT_MSVC_CRTDBG */
-#endif