Adding upstream version 1:2.39.2.upstream/1%2.39.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

15 files changed, 851 insertions, 0 deletions

diff --git a/compat/win32.h b/compat/win32.h
new file mode 100644
index 0000000..a97e880
--- /dev/null
+++ b/compat/win32.h
@@ -0,0 +1,41 @@
+#ifndef WIN32_H
+#define WIN32_H
+
+/* common Win32 functions for MinGW and Cygwin */
+#ifndef GIT_WINDOWS_NATIVE	/* Not defined for Cygwin */
+#include <windows.h>
+#endif
+
+static inline int file_attr_to_st_mode (DWORD attr)
+{
+	int fMode = S_IREAD;
+	if (attr & FILE_ATTRIBUTE_DIRECTORY)
+		fMode |= S_IFDIR;
+	else
+		fMode |= S_IFREG;
+	if (!(attr & FILE_ATTRIBUTE_READONLY))
+		fMode |= S_IWRITE;
+	return fMode;
+}
+
+static inline int get_file_attr(const char *fname, WIN32_FILE_ATTRIBUTE_DATA *fdata)
+{
+	if (GetFileAttributesExA(fname, GetFileExInfoStandard, fdata))
+		return 0;
+
+	switch (GetLastError()) {
+	case ERROR_ACCESS_DENIED:
+	case ERROR_SHARING_VIOLATION:
+	case ERROR_LOCK_VIOLATION:
+	case ERROR_SHARING_BUFFER_EXCEEDED:
+		return EACCES;
+	case ERROR_BUFFER_OVERFLOW:
+		return ENAMETOOLONG;
+	case ERROR_NOT_ENOUGH_MEMORY:
+		return ENOMEM;
+	default:
+		return ENOENT;
+	}
+}
+
+#endif
diff --git a/compat/win32/alloca.h b/compat/win32/alloca.h
new file mode 100644
index 0000000..c0d7985
--- /dev/null
+++ b/compat/win32/alloca.h
@@ -0,0 +1 @@
+#include <malloc.h>
diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
new file mode 100644
index 0000000..52420ec
--- /dev/null
+++ b/compat/win32/dirent.c
@@ -0,0 +1,92 @@
+#include "../../git-compat-util.h"
+
+struct DIR {
+	struct dirent dd_dir; /* includes d_type */
+	HANDLE dd_handle;     /* FindFirstFile handle */
+	int dd_stat;          /* 0-based index */
+};
+
+static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
+{
+	/* convert UTF-16 name to UTF-8 */
+	xwcstoutf(ent->d_name, fdata->cFileName, sizeof(ent->d_name));
+
+	/* Set file type, based on WIN32_FIND_DATA */
+	if (fdata->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+		ent->d_type = DT_DIR;
+	else
+		ent->d_type = DT_REG;
+}
+
+DIR *opendir(const char *name)
+{
+	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
+	WIN32_FIND_DATAW fdata;
+	HANDLE h;
+	int len;
+	DIR *dir;
+
+	/* convert name to UTF-16 and check length < MAX_PATH */
+	if ((len = xutftowcs_path(pattern, name)) < 0)
+		return NULL;
+
+	/* append optional '/' and wildcard '*' */
+	if (len && !is_dir_sep(pattern[len - 1]))
+		pattern[len++] = '/';
+	pattern[len++] = '*';
+	pattern[len] = 0;
+
+	/* open find handle */
+	h = FindFirstFileW(pattern, &fdata);
+	if (h == INVALID_HANDLE_VALUE) {
+		DWORD err = GetLastError();
+		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
+		return NULL;
+	}
+
+	/* initialize DIR structure and copy first dir entry */
+	dir = xmalloc(sizeof(DIR));
+	dir->dd_handle = h;
+	dir->dd_stat = 0;
+	finddata2dirent(&dir->dd_dir, &fdata);
+	return dir;
+}
+
+struct dirent *readdir(DIR *dir)
+{
+	if (!dir) {
+		errno = EBADF; /* No set_errno for mingw */
+		return NULL;
+	}
+
+	/* if first entry, dirent has already been set up by opendir */
+	if (dir->dd_stat) {
+		/* get next entry and convert from WIN32_FIND_DATA to dirent */
+		WIN32_FIND_DATAW fdata;
+		if (FindNextFileW(dir->dd_handle, &fdata)) {
+			finddata2dirent(&dir->dd_dir, &fdata);
+		} else {
+			DWORD lasterr = GetLastError();
+			/* POSIX says you shouldn't set errno when readdir can't
+			   find any more files; so, if another error we leave it set. */
+			if (lasterr != ERROR_NO_MORE_FILES)
+				errno = err_win_to_posix(lasterr);
+			return NULL;
+		}
+	}
+
+	++dir->dd_stat;
+	return &dir->dd_dir;
+}
+
+int closedir(DIR *dir)
+{
+	if (!dir) {
+		errno = EBADF;
+		return -1;
+	}
+
+	FindClose(dir->dd_handle);
+	free(dir);
+	return 0;
+}
diff --git a/compat/win32/dirent.h b/compat/win32/dirent.h
new file mode 100644
index 0000000..058207e
--- /dev/null
+++ b/compat/win32/dirent.h
@@ -0,0 +1,20 @@
+#ifndef DIRENT_H
+#define DIRENT_H
+
+typedef struct DIR DIR;
+
+#define DT_UNKNOWN 0
+#define DT_DIR     1
+#define DT_REG     2
+#define DT_LNK     3
+
+struct dirent {
+	unsigned char d_type;      /* file type to prevent lstat after readdir */
+	char d_name[MAX_PATH * 3]; /* file name (* 3 for UTF-8 conversion) */
+};
+
+DIR *opendir(const char *dirname);
+struct dirent *readdir(DIR *dir);
+int closedir(DIR *dir);
+
+#endif /* DIRENT_H */
diff --git a/compat/win32/flush.c b/compat/win32/flush.c
new file mode 100644
index 0000000..291f90e
--- /dev/null
+++ b/compat/win32/flush.c
@@ -0,0 +1,28 @@
+#include "git-compat-util.h"
+#include <winternl.h>
+#include "lazyload.h"
+
+int win32_fsync_no_flush(int fd)
+{
+       IO_STATUS_BLOCK io_status;
+
+#define FLUSH_FLAGS_FILE_DATA_ONLY 1
+
+       DECLARE_PROC_ADDR(ntdll.dll, NTSTATUS, NTAPI, NtFlushBuffersFileEx,
+			 HANDLE FileHandle, ULONG Flags, PVOID Parameters, ULONG ParameterSize,
+			 PIO_STATUS_BLOCK IoStatusBlock);
+
+       if (!INIT_PROC_ADDR(NtFlushBuffersFileEx)) {
+		errno = ENOSYS;
+		return -1;
+       }
+
+       memset(&io_status, 0, sizeof(io_status));
+       if (NtFlushBuffersFileEx((HANDLE)_get_osfhandle(fd), FLUSH_FLAGS_FILE_DATA_ONLY,
+				NULL, 0, &io_status)) {
+		errno = EINVAL;
+		return -1;
+       }
+
+       return 0;
+}
diff --git a/compat/win32/git.manifest b/compat/win32/git.manifest
new file mode 100644
index 0000000..771e3cc
--- /dev/null
+++ b/compat/win32/git.manifest
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+	<assemblyIdentity type="win32" name="Git" version="0.0.0.1" />
+	<trustInfo xmlns="urn:schemas-microsoft-com:asm.v2">
+		<security>
+			<requestedPrivileges>
+				<requestedExecutionLevel level="asInvoker" uiAccess="false" />
+			</requestedPrivileges>
+		</security>
+	</trustInfo>
+	<compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
+		<application>
+			<!-- Windows Vista -->
+			<supportedOS Id="{e2011457-1546-43c5-a5fe-008deee3d3f0}"/>
+			<!-- Windows 7 -->
+			<supportedOS Id="{35138b9a-5d96-4fbd-8e2d-a2440225f93a}"/>
+			<!-- Windows 8 -->
+			<supportedOS Id="{4a2f28e3-53b9-4441-ba9c-d69d4a4a6e38}"/>
+			<!-- Windows 8.1 -->
+			<supportedOS Id="{1f676c76-80e1-4239-95bb-83d0f6d0da78}"/>
+			<!-- Windows 10 -->
+			<supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}"/>
+		</application>
+	</compatibility>
+</assembly>
diff --git a/compat/win32/lazyload.h b/compat/win32/lazyload.h
new file mode 100644
index 0000000..f2bb96c
--- /dev/null
+++ b/compat/win32/lazyload.h
@@ -0,0 +1,61 @@
+#ifndef LAZYLOAD_H
+#define LAZYLOAD_H
+
+/*
+ * A pair of macros to simplify loading of DLL functions. Example:
+ *
+ *   DECLARE_PROC_ADDR(kernel32.dll, BOOL, WINAPI, CreateHardLinkW,
+ *                     LPCWSTR, LPCWSTR, LPSECURITY_ATTRIBUTES);
+ *
+ *   if (!INIT_PROC_ADDR(CreateHardLinkW))
+ *           return error("Could not find CreateHardLinkW() function";
+ *
+ *   if (!CreateHardLinkW(source, target, NULL))
+ *           return error("could not create hardlink from %S to %S",
+ *                        source, target);
+ */
+
+typedef void (*FARVOIDPROC)(void);
+
+struct proc_addr {
+	const char *const dll;
+	const char *const function;
+	FARVOIDPROC pfunction;
+	unsigned initialized : 1;
+};
+
+/* Declares a function to be loaded dynamically from a DLL. */
+#define DECLARE_PROC_ADDR(dll, rettype, convention, function, ...) \
+	static struct proc_addr proc_addr_##function = \
+	{ #dll, #function, NULL, 0 }; \
+	typedef rettype (convention *proc_type_##function)(__VA_ARGS__); \
+	static proc_type_##function function
+
+/*
+ * Loads a function from a DLL (once-only).
+ * Returns non-NULL function pointer on success.
+ * Returns NULL + errno == ENOSYS on failure.
+ * This function is not thread-safe.
+ */
+#define INIT_PROC_ADDR(function) \
+	(function = (proc_type_##function)get_proc_addr(&proc_addr_##function))
+
+static inline FARVOIDPROC get_proc_addr(struct proc_addr *proc)
+{
+	/* only do this once */
+	if (!proc->initialized) {
+		HANDLE hnd;
+		proc->initialized = 1;
+		hnd = LoadLibraryExA(proc->dll, NULL,
+				     LOAD_LIBRARY_SEARCH_SYSTEM32);
+		if (hnd)
+			proc->pfunction = (FARVOIDPROC)GetProcAddress(hnd,
+							proc->function);
+	}
+	/* set ENOSYS if DLL or function was not found */
+	if (!proc->pfunction)
+		errno = ENOSYS;
+	return proc->pfunction;
+}
+
+#endif
diff --git a/compat/win32/path-utils.c b/compat/win32/path-utils.c
new file mode 100644
index 0000000..ebf2f12
--- /dev/null
+++ b/compat/win32/path-utils.c
@@ -0,0 +1,52 @@
+#include "../../git-compat-util.h"
+
+int win32_has_dos_drive_prefix(const char *path)
+{
+	int i;
+
+	/*
+	 * Does it start with an ASCII letter (i.e. highest bit not set),
+	 * followed by a colon?
+	 */
+	if (!(0x80 & (unsigned char)*path))
+		return *path && path[1] == ':' ? 2 : 0;
+
+	/*
+	 * While drive letters must be letters of the English alphabet, it is
+	 * possible to assign virtually _any_ Unicode character via `subst` as
+	 * a drive letter to "virtual drives". Even `1`, or `ä`. Or fun stuff
+	 * like this:
+	 *
+	 *      subst ֍: %USERPROFILE%\Desktop
+	 */
+	for (i = 1; i < 4 && (0x80 & (unsigned char)path[i]); i++)
+		; /* skip first UTF-8 character */
+	return path[i] == ':' ? i + 1 : 0;
+}
+
+int win32_skip_dos_drive_prefix(char **path)
+{
+	int ret = has_dos_drive_prefix(*path);
+	*path += ret;
+	return ret;
+}
+
+int win32_offset_1st_component(const char *path)
+{
+	char *pos = (char *)path;
+
+	/* unc paths */
+	if (!skip_dos_drive_prefix(&pos) &&
+			is_dir_sep(pos[0]) && is_dir_sep(pos[1])) {
+		/* skip server name */
+		pos = strpbrk(pos + 2, "\\/");
+		if (!pos)
+			return 0; /* Error: malformed unc path */
+
+		do {
+			pos++;
+		} while (*pos && !is_dir_sep(*pos));
+	}
+
+	return pos + is_dir_sep(*pos) - path;
+}
diff --git a/compat/win32/path-utils.h b/compat/win32/path-utils.h
new file mode 100644
index 0000000..65fa3b9
--- /dev/null
+++ b/compat/win32/path-utils.h
@@ -0,0 +1,33 @@
+#ifndef WIN32_PATH_UTILS_H
+#define WIN32_PATH_UTILS_H
+
+int win32_has_dos_drive_prefix(const char *path);
+#define has_dos_drive_prefix win32_has_dos_drive_prefix
+
+int win32_skip_dos_drive_prefix(char **path);
+#define skip_dos_drive_prefix win32_skip_dos_drive_prefix
+#define is_dir_sep is_xplatform_dir_sep
+static inline char *win32_find_last_dir_sep(const char *path)
+{
+	char *ret = NULL;
+	for (; *path; ++path)
+		if (is_dir_sep(*path))
+			ret = (char *)path;
+	return ret;
+}
+#define find_last_dir_sep win32_find_last_dir_sep
+static inline int win32_has_dir_sep(const char *path)
+{
+	/*
+	 * See how long the non-separator part of the given path is, and
+	 * if and only if it covers the whole path (i.e. path[len] is NUL),
+	 * there is no separator in the path---otherwise there is a separator.
+	 */
+	size_t len = strcspn(path, "/\\");
+	return !!path[len];
+}
+#define has_dir_sep(path) win32_has_dir_sep(path)
+int win32_offset_1st_component(const char *path);
+#define offset_1st_component win32_offset_1st_component
+
+#endif
diff --git a/compat/win32/pthread.c b/compat/win32/pthread.c
new file mode 100644
index 0000000..2e7eead
--- /dev/null
+++ b/compat/win32/pthread.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2009 Andrzej K. Haczewski <ahaczewski@gmail.com>
+ *
+ * DISCLAIMER: The implementation is Git-specific, it is subset of original
+ * Pthreads API, without lots of other features that Git doesn't use.
+ * Git also makes sure that the passed arguments are valid, so there's
+ * no need for double-checking.
+ */
+
+#include "../../git-compat-util.h"
+#include "pthread.h"
+
+#include <errno.h>
+#include <limits.h>
+
+static unsigned __stdcall win32_start_routine(void *arg)
+{
+	pthread_t *thread = arg;
+	thread->tid = GetCurrentThreadId();
+	thread->arg = thread->start_routine(thread->arg);
+	return 0;
+}
+
+int pthread_create(pthread_t *thread, const void *unused,
+		   void *(*start_routine)(void*), void *arg)
+{
+	thread->arg = arg;
+	thread->start_routine = start_routine;
+	thread->handle = (HANDLE)
+		_beginthreadex(NULL, 0, win32_start_routine, thread, 0, NULL);
+
+	if (!thread->handle)
+		return errno;
+	else
+		return 0;
+}
+
+int win32_pthread_join(pthread_t *thread, void **value_ptr)
+{
+	DWORD result = WaitForSingleObject(thread->handle, INFINITE);
+	switch (result) {
+		case WAIT_OBJECT_0:
+			if (value_ptr)
+				*value_ptr = thread->arg;
+			return 0;
+		case WAIT_ABANDONED:
+			return EINVAL;
+		default:
+			return err_win_to_posix(GetLastError());
+	}
+}
+
+pthread_t pthread_self(void)
+{
+	pthread_t t = { NULL };
+	t.tid = GetCurrentThreadId();
+	return t;
+}
diff --git a/compat/win32/pthread.h b/compat/win32/pthread.h
new file mode 100644
index 0000000..737983d
--- /dev/null
+++ b/compat/win32/pthread.h
@@ -0,0 +1,100 @@
+/*
+ * Header used to adapt pthread-based POSIX code to Windows API threads.
+ *
+ * Copyright (C) 2009 Andrzej K. Haczewski <ahaczewski@gmail.com>
+ */
+
+#ifndef PTHREAD_H
+#define PTHREAD_H
+
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+
+#include <windows.h>
+
+/*
+ * Defines that adapt Windows API threads to pthreads API
+ */
+#define pthread_mutex_t CRITICAL_SECTION
+
+static inline int return_0(int i) {
+	return 0;
+}
+#define pthread_mutex_init(a,b) return_0((InitializeCriticalSection((a)), 0))
+#define pthread_mutex_destroy(a) DeleteCriticalSection((a))
+#define pthread_mutex_lock EnterCriticalSection
+#define pthread_mutex_unlock LeaveCriticalSection
+
+typedef int pthread_mutexattr_t;
+#define pthread_mutexattr_init(a) (*(a) = 0)
+#define pthread_mutexattr_destroy(a) do {} while (0)
+#define pthread_mutexattr_settype(a, t) 0
+#define PTHREAD_MUTEX_RECURSIVE 0
+
+#define pthread_cond_t CONDITION_VARIABLE
+
+#define pthread_cond_init(a,b) InitializeConditionVariable((a))
+#define pthread_cond_destroy(a) do {} while (0)
+#define pthread_cond_wait(a,b) return_0(SleepConditionVariableCS((a), (b), INFINITE))
+#define pthread_cond_signal WakeConditionVariable
+#define pthread_cond_broadcast WakeAllConditionVariable
+
+/*
+ * Simple thread creation implementation using pthread API
+ */
+typedef struct {
+	HANDLE handle;
+	void *(*start_routine)(void*);
+	void *arg;
+	DWORD tid;
+} pthread_t;
+
+int pthread_create(pthread_t *thread, const void *unused,
+		   void *(*start_routine)(void*), void *arg);
+
+/*
+ * To avoid the need of copying a struct, we use small macro wrapper to pass
+ * pointer to win32_pthread_join instead.
+ */
+#define pthread_join(a, b) win32_pthread_join(&(a), (b))
+
+int win32_pthread_join(pthread_t *thread, void **value_ptr);
+
+#define pthread_equal(t1, t2) ((t1).tid == (t2).tid)
+pthread_t pthread_self(void);
+
+static inline void NORETURN pthread_exit(void *ret)
+{
+	ExitThread((DWORD)(intptr_t)ret);
+}
+
+typedef DWORD pthread_key_t;
+static inline int pthread_key_create(pthread_key_t *keyp, void (*destructor)(void *value))
+{
+	return (*keyp = TlsAlloc()) == TLS_OUT_OF_INDEXES ? EAGAIN : 0;
+}
+
+static inline int pthread_key_delete(pthread_key_t key)
+{
+	return TlsFree(key) ? 0 : EINVAL;
+}
+
+static inline int pthread_setspecific(pthread_key_t key, const void *value)
+{
+	return TlsSetValue(key, (void *)value) ? 0 : EINVAL;
+}
+
+static inline void *pthread_getspecific(pthread_key_t key)
+{
+	return TlsGetValue(key);
+}
+
+#ifndef __MINGW64_VERSION_MAJOR
+static inline int pthread_sigmask(int how, const sigset_t *set, sigset_t *oset)
+{
+	return 0;
+}
+#endif
+
+#endif /* PTHREAD_H */
diff --git a/compat/win32/syslog.c b/compat/win32/syslog.c
new file mode 100644
index 0000000..0af18d8
--- /dev/null
+++ b/compat/win32/syslog.c
@@ -0,0 +1,83 @@
+#include "../../git-compat-util.h"
+
+static HANDLE ms_eventlog;
+
+void openlog(const char *ident, int logopt, int facility)
+{
+	if (ms_eventlog)
+		return;
+
+	ms_eventlog = RegisterEventSourceA(NULL, ident);
+
+	if (!ms_eventlog)
+		warning("RegisterEventSource() failed: %lu", GetLastError());
+}
+
+void syslog(int priority, const char *fmt, ...)
+{
+	WORD logtype;
+	char *str, *pos;
+	int str_len;
+	va_list ap;
+
+	if (!ms_eventlog)
+		return;
+
+	va_start(ap, fmt);
+	str_len = vsnprintf(NULL, 0, fmt, ap);
+	va_end(ap);
+
+	if (str_len < 0) {
+		warning_errno("vsnprintf failed");
+		return;
+	}
+
+	str = malloc(st_add(str_len, 1));
+	if (!str) {
+		warning_errno("malloc failed");
+		return;
+	}
+
+	va_start(ap, fmt);
+	vsnprintf(str, str_len + 1, fmt, ap);
+	va_end(ap);
+
+	while ((pos = strstr(str, "%1")) != NULL) {
+		size_t offset = pos - str;
+		char *new_pos;
+		char *oldstr = str;
+		str = realloc(str, st_add(++str_len, 1));
+		if (!str) {
+			free(oldstr);
+			warning_errno("realloc failed");
+			return;
+		}
+		new_pos = str + offset;
+		memmove(new_pos + 2, new_pos + 1, strlen(new_pos));
+		new_pos[1] = ' ';
+	}
+
+	switch (priority) {
+	case LOG_EMERG:
+	case LOG_ALERT:
+	case LOG_CRIT:
+	case LOG_ERR:
+		logtype = EVENTLOG_ERROR_TYPE;
+		break;
+
+	case LOG_WARNING:
+		logtype = EVENTLOG_WARNING_TYPE;
+		break;
+
+	case LOG_NOTICE:
+	case LOG_INFO:
+	case LOG_DEBUG:
+	default:
+		logtype = EVENTLOG_INFORMATION_TYPE;
+		break;
+	}
+
+	ReportEventA(ms_eventlog, logtype, 0, 0, NULL, 1, 0,
+	    (const char **)&str, NULL);
+	free(str);
+}
diff --git a/compat/win32/syslog.h b/compat/win32/syslog.h
new file mode 100644
index 0000000..70daa7c
--- /dev/null
+++ b/compat/win32/syslog.h
@@ -0,0 +1,20 @@
+#ifndef SYSLOG_H
+#define SYSLOG_H
+
+#define LOG_PID     0x01
+
+#define LOG_EMERG   0
+#define LOG_ALERT   1
+#define LOG_CRIT    2
+#define LOG_ERR     3
+#define LOG_WARNING 4
+#define LOG_NOTICE  5
+#define LOG_INFO    6
+#define LOG_DEBUG   7
+
+#define LOG_DAEMON  (3<<3)
+
+void openlog(const char *ident, int logopt, int facility);
+void syslog(int priority, const char *fmt, ...);
+
+#endif /* SYSLOG_H */
diff --git a/compat/win32/trace2_win32_process_info.c b/compat/win32/trace2_win32_process_info.c
new file mode 100644
index 0000000..a53fd92
--- /dev/null
+++ b/compat/win32/trace2_win32_process_info.c
@@ -0,0 +1,191 @@
+#include "../../cache.h"
+#include "../../json-writer.h"
+#include "lazyload.h"
+#include <Psapi.h>
+#include <tlHelp32.h>
+
+/*
+ * An arbitrarily chosen value to limit the size of the ancestor
+ * array built in git_processes().
+ */
+#define NR_PIDS_LIMIT 10
+
+/*
+ * Find the process data for the given PID in the given snapshot
+ * and update the PROCESSENTRY32 data.
+ */
+static int find_pid(DWORD pid, HANDLE hSnapshot, PROCESSENTRY32 *pe32)
+{
+	pe32->dwSize = sizeof(PROCESSENTRY32);
+
+	if (Process32First(hSnapshot, pe32)) {
+		do {
+			if (pe32->th32ProcessID == pid)
+				return 1;
+		} while (Process32Next(hSnapshot, pe32));
+	}
+	return 0;
+}
+
+/*
+ * Accumulate JSON array of our parent processes:
+ *     [
+ *         exe-name-parent,
+ *         exe-name-grand-parent,
+ *         ...
+ *     ]
+ *
+ * Note: we only report the filename of the process executable; the
+ *       only way to get its full pathname is to use OpenProcess()
+ *       and GetModuleFileNameEx() or QueryfullProcessImageName()
+ *       and that seems rather expensive (on top of the cost of
+ *       getting the snapshot).
+ *
+ * Note: we compute the set of parent processes by walking the PPID
+ *       link in each visited PROCESSENTRY32 record.  This search
+ *       stops when an ancestor process is not found in the snapshot
+ *       (because it exited before the current or intermediate parent
+ *       process exited).
+ *
+ *       This search may compute an incorrect result if the PPID link
+ *       refers to the PID of an exited parent and that PID has been
+ *       recycled and given to a new unrelated process.
+ *
+ *       Worse, it is possible for a child or descendant of the
+ *       current process to be given the recycled PID and cause a
+ *       PPID-cycle.  This would cause an infinite loop building our
+ *       parent process array.
+ *
+ * Note: for completeness, the "System Idle" process has PID=0 and
+ *       PPID=0 and could cause another PPID-cycle.  We don't expect
+ *       Git to be a descendant of the idle process, but because of
+ *       PID recycling, it might be possible to get a PPID link value
+ *       of 0.  This too would cause an infinite loop.
+ *
+ * Therefore, we keep an array of the visited PPIDs to guard against
+ * cycles.
+ *
+ * We use a fixed-size array rather than ALLOC_GROW to keep things
+ * simple and avoid the alloc/realloc overhead.  It is OK if we
+ * truncate the search and return a partial answer.
+ */
+static void get_processes(struct json_writer *jw, HANDLE hSnapshot)
+{
+	PROCESSENTRY32 pe32;
+	DWORD pid;
+	DWORD pid_list[NR_PIDS_LIMIT];
+	int k, nr_pids = 0;
+
+	pid = GetCurrentProcessId();
+	while (find_pid(pid, hSnapshot, &pe32)) {
+		/* Only report parents. Omit self from the JSON output. */
+		if (nr_pids)
+			jw_array_string(jw, pe32.szExeFile);
+
+		/* Check for cycle in snapshot. (Yes, it happened.) */
+		for (k = 0; k < nr_pids; k++)
+			if (pid == pid_list[k]) {
+				jw_array_string(jw, "(cycle)");
+				return;
+			}
+
+		if (nr_pids == NR_PIDS_LIMIT) {
+			jw_array_string(jw, "(truncated)");
+			return;
+		}
+
+		pid_list[nr_pids++] = pid;
+
+		pid = pe32.th32ParentProcessID;
+	}
+}
+
+/*
+ * Emit JSON data for the current and parent processes.  Individual
+ * trace2 targets can decide how to actually print it.
+ */
+static void get_ancestry(void)
+{
+	HANDLE hSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
+
+	if (hSnapshot != INVALID_HANDLE_VALUE) {
+		struct json_writer jw = JSON_WRITER_INIT;
+
+		jw_array_begin(&jw, 0);
+		get_processes(&jw, hSnapshot);
+		jw_end(&jw);
+
+		trace2_data_json("process", the_repository, "windows/ancestry",
+				 &jw);
+
+		jw_release(&jw);
+		CloseHandle(hSnapshot);
+	}
+}
+
+/*
+ * Is a debugger attached to the current process?
+ *
+ * This will catch debug runs (where the debugger started the process).
+ * This is the normal case.  Since this code is called during our startup,
+ * it will not report instances where a debugger is attached dynamically
+ * to a running git process, but that is relatively rare.
+ */
+static void get_is_being_debugged(void)
+{
+	if (IsDebuggerPresent())
+		trace2_data_intmax("process", the_repository,
+				   "windows/debugger_present", 1);
+}
+
+/*
+ * Emit JSON data with the peak memory usage of the current process.
+ */
+static void get_peak_memory_info(void)
+{
+	DECLARE_PROC_ADDR(psapi.dll, BOOL, WINAPI, GetProcessMemoryInfo,
+			  HANDLE, PPROCESS_MEMORY_COUNTERS, DWORD);
+
+	if (INIT_PROC_ADDR(GetProcessMemoryInfo)) {
+		PROCESS_MEMORY_COUNTERS pmc;
+
+		if (GetProcessMemoryInfo(GetCurrentProcess(), &pmc,
+					 sizeof(pmc))) {
+			struct json_writer jw = JSON_WRITER_INIT;
+
+			jw_object_begin(&jw, 0);
+
+#define KV(kv) #kv, (intmax_t)pmc.kv
+
+			jw_object_intmax(&jw, KV(PageFaultCount));
+			jw_object_intmax(&jw, KV(PeakWorkingSetSize));
+			jw_object_intmax(&jw, KV(PeakPagefileUsage));
+
+			jw_end(&jw);
+
+			trace2_data_json("process", the_repository,
+					 "windows/memory", &jw);
+			jw_release(&jw);
+		}
+	}
+}
+
+void trace2_collect_process_info(enum trace2_process_info_reason reason)
+{
+	if (!trace2_is_enabled())
+		return;
+
+	switch (reason) {
+	case TRACE2_PROCESS_INFO_STARTUP:
+		get_is_being_debugged();
+		get_ancestry();
+		return;
+
+	case TRACE2_PROCESS_INFO_EXIT:
+		get_peak_memory_info();
+		return;
+
+	default:
+		BUG("trace2_collect_process_info: unknown reason '%d'", reason);
+	}
+}
diff --git a/compat/win32mmap.c b/compat/win32mmap.c
new file mode 100644
index 0000000..519d51f
--- /dev/null
+++ b/compat/win32mmap.c
@@ -0,0 +1,46 @@
+#include "../git-compat-util.h"
+
+void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
+{
+	HANDLE osfhandle, hmap;
+	void *temp;
+	LARGE_INTEGER len;
+	uint64_t o = offset;
+	uint32_t l = o & 0xFFFFFFFF;
+	uint32_t h = (o >> 32) & 0xFFFFFFFF;
+
+	osfhandle = (HANDLE)_get_osfhandle(fd);
+	if (!GetFileSizeEx(osfhandle, &len))
+		die("mmap: could not determine filesize");
+
+	if ((length + offset) > len.QuadPart)
+		length = xsize_t(len.QuadPart - offset);
+
+	if (!(flags & MAP_PRIVATE))
+		die("Invalid usage of mmap when built with USE_WIN32_MMAP");
+
+	hmap = CreateFileMapping(osfhandle, NULL,
+		prot == PROT_READ ? PAGE_READONLY : PAGE_WRITECOPY, 0, 0, NULL);
+
+	if (!hmap) {
+		errno = EINVAL;
+		return MAP_FAILED;
+	}
+
+	temp = MapViewOfFileEx(hmap, prot == PROT_READ ?
+			FILE_MAP_READ : FILE_MAP_COPY, h, l, length, start);
+
+	if (!CloseHandle(hmap))
+		warning("unable to close file mapping handle");
+
+	if (temp)
+		return temp;
+
+	errno = GetLastError() == ERROR_COMMITMENT_LIMIT ? EFBIG : EINVAL;
+	return MAP_FAILED;
+}
+
+int git_munmap(void *start, size_t length)
+{
+	return !UnmapViewOfFile(start);
+}