utf8: add conversion with size and refactor names

Add functions to use convert a string with length, instead of assuming
NUL termination.

In addition, move the utf8 to 16 conversion routines into the `git_utf8`
namespace instead of using namespaceless `git__` prefixed names.

Author: ethomson

src/libgit2/streams/schannel.c

@@ -661,7 +661,7 @@ static int schannel_stream_wrap(
 	st->io = in;
 	st->owned = owned;
 
-	if (git__utf8_to_16_alloc(&st->host_w, host) < 0) {
+	if (git_utf8_to_16_alloc(&st->host_w, host) < 0) {
 		git__free(st);
 		return -1;
 	}

src/libgit2/transports/winhttp.c

@@ -158,10 +158,10 @@ static int apply_userpass_credentials(HINTERNET request, DWORD target, int mecha
 		goto done;
 	}
 
-	if ((error = user_len = git__utf8_to_16_alloc(&user, c->username)) < 0)
+	if ((error = user_len = git_utf8_to_16_alloc(&user, c->username)) < 0)
 		goto done;
 
-	if ((error = pass_len = git__utf8_to_16_alloc(&pass, c->password)) < 0)
+	if ((error = pass_len = git_utf8_to_16_alloc(&pass, c->password)) < 0)
 		goto done;
 
 	if (!WinHttpSetCredentials(request, target, native_scheme, user, pass, NULL)) {
@@ -242,7 +242,7 @@ static int acquire_fallback_cred(
 		HRESULT hCoInitResult;
 
 		/* Convert URL to wide characters */
-		if (git__utf8_to_16_alloc(&wide_url, url) < 0) {
+		if (git_utf8_to_16_alloc(&wide_url, url) < 0) {
 			git_error_set(GIT_ERROR_OS, "failed to convert string to wide form");
 			return -1;
 		}
@@ -397,7 +397,7 @@ static int winhttp_stream_connect(winhttp_stream *s)
 		return -1;
 
 	/* Convert URL to wide characters */
-	if (git__utf8_to_16_alloc(&s->request_uri, git_str_cstr(&buf)) < 0) {
+	if (git_utf8_to_16_alloc(&s->request_uri, git_str_cstr(&buf)) < 0) {
 		git_error_set(GIT_ERROR_OS, "failed to convert string to wide form");
 		goto on_error;
 	}
@@ -473,7 +473,7 @@ static int winhttp_stream_connect(winhttp_stream *s)
 		}
 
 		/* Convert URL to wide characters */
-		error = git__utf8_to_16_alloc(&proxy_wide, processed_url.ptr);
+		error = git_utf8_to_16_alloc(&proxy_wide, processed_url.ptr);
 		git_str_dispose(&processed_url);
 		if (error < 0)
 			goto on_error;
@@ -531,7 +531,7 @@ static int winhttp_stream_connect(winhttp_stream *s)
 			s->service) < 0)
 			goto on_error;
 
-		if (git__utf8_to_16(ct, MAX_CONTENT_TYPE_LEN, git_str_cstr(&buf)) < 0) {
+		if (git_utf8_to_16(ct, MAX_CONTENT_TYPE_LEN, git_str_cstr(&buf)) < 0) {
 			git_error_set(GIT_ERROR_OS, "failed to convert content-type to wide characters");
 			goto on_error;
 		}
@@ -548,7 +548,7 @@ static int winhttp_stream_connect(winhttp_stream *s)
 			s->service) < 0)
 			goto on_error;
 
-		if (git__utf8_to_16(ct, MAX_CONTENT_TYPE_LEN, git_str_cstr(&buf)) < 0) {
+		if (git_utf8_to_16(ct, MAX_CONTENT_TYPE_LEN, git_str_cstr(&buf)) < 0) {
 			git_error_set(GIT_ERROR_OS, "failed to convert accept header to wide characters");
 			goto on_error;
 		}
@@ -568,7 +568,7 @@ static int winhttp_stream_connect(winhttp_stream *s)
 			git_str_puts(&buf, t->owner->connect_opts.custom_headers.strings[i]);
 
 			/* Convert header to wide characters */
-			if ((error = git__utf8_to_16_alloc(&custom_header_wide, git_str_cstr(&buf))) < 0)
+			if ((error = git_utf8_to_16_alloc(&custom_header_wide, git_str_cstr(&buf))) < 0)
 				goto on_error;
 
 			if (!WinHttpAddRequestHeaders(s->request, custom_header_wide, (ULONG)-1L,
@@ -783,7 +783,7 @@ static int winhttp_connect(
 	}
 
 	/* Prepare host */
-	if (git__utf8_to_16_alloc(&wide_host, host) < 0) {
+	if (git_utf8_to_16_alloc(&wide_host, host) < 0) {
 		git_error_set(GIT_ERROR_OS, "unable to convert host to wide characters");
 		goto on_error;
 	}
@@ -792,7 +792,7 @@ static int winhttp_connect(
 	if (git_http__user_agent(&ua) < 0)
 		goto on_error;
 
-	if (git__utf8_to_16_alloc(&wide_ua, git_str_cstr(&ua)) < 0) {
+	if (git_utf8_to_16_alloc(&wide_ua, git_str_cstr(&ua)) < 0) {
 		git_error_set(GIT_ERROR_OS, "unable to convert host to wide characters");
 		goto on_error;
 	}
@@ -1182,7 +1182,7 @@ static int winhttp_stream_read(
 			}
 
 			/* Convert the Location header to UTF-8 */
-			if (git__utf16_to_8_alloc(&location8, location) < 0) {
+			if (git_utf8_from_16_alloc(&location8, location) < 0) {
 				git_error_set(GIT_ERROR_OS, "failed to convert Location header to UTF-8");
 				git__free(location);
 				return -1;
@@ -1254,7 +1254,7 @@ static int winhttp_stream_read(
 		else
 			p_snprintf(expected_content_type_8, MAX_CONTENT_TYPE_LEN, "application/x-git-%s-advertisement", s->service);
 
-		if (git__utf8_to_16(expected_content_type, MAX_CONTENT_TYPE_LEN, expected_content_type_8) < 0) {
+		if (git_utf8_to_16(expected_content_type, MAX_CONTENT_TYPE_LEN, expected_content_type_8) < 0) {
 			git_error_set(GIT_ERROR_OS, "failed to convert expected content-type to wide characters");
 			return -1;
 		}

src/util/fs_path.c

@@ -2015,7 +2015,7 @@ int git_fs_path_find_executable(git_str *fullpath, const char *executable)
 	git_win32_path fullpath_w, executable_w;
 	int error;
 
-	if (git__utf8_to_16(executable_w, GIT_WIN_PATH_MAX, executable) < 0)
+	if (git_utf8_to_16(executable_w, GIT_WIN_PATH_MAX, executable) < 0)
 		return -1;
 
 	error = git_win32_path_find_executable(fullpath_w, executable_w);

src/util/util.c

@@ -743,7 +743,7 @@ int git__getenv(git_str *out, const char *name)
 
 	git_str_clear(out);
 
-	if (git__utf8_to_16_alloc(&wide_name, name) < 0)
+	if (git_utf8_to_16_alloc(&wide_name, name) < 0)
 		return -1;
 
 	if ((value_len = GetEnvironmentVariableW(wide_name, NULL, 0)) > 0) {

src/util/win32/error.c

@@ -43,7 +43,7 @@ char *git_win32_get_error_message(DWORD error_code)
 		(LPWSTR)&lpMsgBuf, 0, NULL)) {
 		/* Convert the message to UTF-8. If this fails, we will
 		 * return NULL, which is a condition expected by the caller */
-		if (git__utf16_to_8_alloc(&utf8_msg, lpMsgBuf) < 0)
+		if (git_utf8_from_16_alloc(&utf8_msg, lpMsgBuf) < 0)
 			utf8_msg = NULL;
 
 		LocalFree(lpMsgBuf);

src/util/win32/path_w32.c

@@ -336,13 +336,13 @@ int git_win32_path_from_utf8(git_win32_path out, const char *src)
 
 	/* See if this is an absolute path (beginning with a drive letter) */
 	if (git_fs_path_is_absolute(src)) {
-		if (git__utf8_to_16(dest, GIT_WIN_PATH_MAX, src) < 0)
+		if (git_utf8_to_16(dest, GIT_WIN_PATH_MAX, src) < 0)
 			goto on_error;
 	}
 	/* File-prefixed NT-style paths beginning with \\?\ */
 	else if (path__is_nt_namespace(src)) {
 		/* Skip the NT prefix, the destination already contains it */
-		if (git__utf8_to_16(dest, GIT_WIN_PATH_MAX, src + PATH__NT_NAMESPACE_LEN) < 0)
+		if (git_utf8_to_16(dest, GIT_WIN_PATH_MAX, src + PATH__NT_NAMESPACE_LEN) < 0)
 			goto on_error;
 	}
 	/* UNC paths */
@@ -351,7 +351,7 @@ int git_win32_path_from_utf8(git_win32_path out, const char *src)
 		dest += 4;
 
 		/* Skip the leading "\\" */
-		if (git__utf8_to_16(dest, GIT_WIN_PATH_MAX - 2, src + 2) < 0)
+		if (git_utf8_to_16(dest, GIT_WIN_PATH_MAX - 2, src + 2) < 0)
 			goto on_error;
 	}
 	/* Absolute paths omitting the drive letter */
@@ -365,7 +365,7 @@ int git_win32_path_from_utf8(git_win32_path out, const char *src)
 		}
 
 		/* Skip the drive letter specification ("C:") */
-		if (git__utf8_to_16(dest + 2, GIT_WIN_PATH_MAX - 2, src) < 0)
+		if (git_utf8_to_16(dest + 2, GIT_WIN_PATH_MAX - 2, src) < 0)
 			goto on_error;
 	}
 	/* Relative paths */
@@ -377,7 +377,7 @@ int git_win32_path_from_utf8(git_win32_path out, const char *src)
 
 		dest[cwd_len++] = L'\\';
 
-		if (git__utf8_to_16(dest + cwd_len, GIT_WIN_PATH_MAX - cwd_len, src) < 0)
+		if (git_utf8_to_16(dest + cwd_len, GIT_WIN_PATH_MAX - cwd_len, src) < 0)
 			goto on_error;
 	}
 
@@ -404,7 +404,7 @@ int git_win32_path_relative_from_utf8(git_win32_path out, const char *src)
 		return git_win32_path_from_utf8(out, src);
 	}
 
-	if ((len = git__utf8_to_16(dest, GIT_WIN_PATH_MAX, src)) < 0)
+	if ((len = git_utf8_to_16(dest, GIT_WIN_PATH_MAX, src)) < 0)
 		return -1;
 
 	for (p = dest; p < (dest + len); p++) {
@@ -433,7 +433,7 @@ int git_win32_path_to_utf8(git_win32_utf8_path dest, const wchar_t *src)
 		}
 	}
 
-	if ((len = git__utf16_to_8(out, GIT_WIN_PATH_UTF8, src)) < 0)
+	if ((len = git_utf8_from_16(out, GIT_WIN_PATH_UTF8, src)) < 0)
 		return len;
 
 	git_fs_path_mkposix(dest);
@@ -471,7 +471,7 @@ char *git_win32_path_8dot3_name(const char *path)
 	if (namelen > 12 || (shortname = git__malloc(namelen + 1)) == NULL)
 		return NULL;
 
-	if ((len = git__utf16_to_8(shortname, namelen + 1, start)) < 0)
+	if ((len = git_utf8_from_16(shortname, namelen + 1, start)) < 0)
 		return NULL;
 
 	return shortname;

src/util/win32/posix_w32.c

@@ -649,7 +649,7 @@ int p_getcwd(char *buffer_out, size_t size)
 	git_win32_path_remove_namespace(cwd, wcslen(cwd));
 
 	/* Convert the working directory back to UTF-8 */
-	if (git__utf16_to_8(buffer_out, size, cwd) < 0) {
+	if (git_utf8_from_16(buffer_out, size, cwd) < 0) {
 		DWORD code = GetLastError();
 
 		if (code == ERROR_INSUFFICIENT_BUFFER)