app: add code for macOS and Windows apps under 'app' (#12933)

* app: add code for macOS and Windows apps under 'app'

* app: add readme

* app: windows and linux only for now

* ci: fix ui CI validation

---------

Co-authored-by: jmorganca <jmorganca@gmail.com>

app/server/server_windows.go

@@ -0,0 +1,149 @@
+package server
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"golang.org/x/sys/windows"
+)
+
+var (
+	pidFile       = filepath.Join(os.Getenv("LOCALAPPDATA"), "Ollama", "ollama.pid")
+	serverLogPath = filepath.Join(os.Getenv("LOCALAPPDATA"), "Ollama", "server.log")
+)
+
+func commandContext(ctx context.Context, name string, arg ...string) *exec.Cmd {
+	cmd := exec.CommandContext(ctx, name, arg...)
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		HideWindow:    true,
+		CreationFlags: windows.CREATE_NEW_PROCESS_GROUP,
+	}
+
+	return cmd
+}
+
+func terminate(proc *os.Process) error {
+	dll, err := windows.LoadDLL("kernel32.dll")
+	if err != nil {
+		return err
+	}
+	defer dll.Release()
+
+	pid := proc.Pid
+
+	f, err := dll.FindProc("AttachConsole")
+	if err != nil {
+		return err
+	}
+
+	r1, _, err := f.Call(uintptr(pid))
+	if r1 == 0 && err != syscall.ERROR_ACCESS_DENIED {
+		return err
+	}
+
+	f, err = dll.FindProc("SetConsoleCtrlHandler")
+	if err != nil {
+		return err
+	}
+
+	r1, _, err = f.Call(0, 1)
+	if r1 == 0 {
+		return err
+	}
+
+	f, err = dll.FindProc("GenerateConsoleCtrlEvent")
+	if err != nil {
+		return err
+	}
+
+	r1, _, err = f.Call(windows.CTRL_BREAK_EVENT, uintptr(pid))
+	if r1 == 0 {
+		return err
+	}
+
+	r1, _, err = f.Call(windows.CTRL_C_EVENT, uintptr(pid))
+	if r1 == 0 {
+		return err
+	}
+
+	return nil
+}
+
+const STILL_ACTIVE = 259
+
+func terminated(pid int) (bool, error) {
+	hProcess, err := windows.OpenProcess(windows.PROCESS_QUERY_INFORMATION, false, uint32(pid))
+	if err != nil {
+		if errno, ok := err.(windows.Errno); ok && errno == windows.ERROR_INVALID_PARAMETER {
+			return true, nil
+		}
+		return false, fmt.Errorf("failed to open process: %v", err)
+	}
+	defer windows.CloseHandle(hProcess)
+
+	var exitCode uint32
+	err = windows.GetExitCodeProcess(hProcess, &exitCode)
+	if err != nil {
+		return false, fmt.Errorf("failed to get exit code: %v", err)
+	}
+
+	if exitCode == STILL_ACTIVE {
+		return false, nil
+	}
+
+	return true, nil
+}
+
+// reapServers kills all ollama processes except our own
+func reapServers() error {
+	// Get current process ID to avoid killing ourselves
+	currentPID := os.Getpid()
+
+	// Use wmic to find ollama processes
+	cmd := exec.Command("wmic", "process", "where", "name='ollama.exe'", "get", "ProcessId")
+	cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
+	output, err := cmd.Output()
+	if err != nil {
+		// No ollama processes found
+		slog.Debug("no ollama processes found")
+		return nil //nolint:nilerr
+	}
+
+	lines := strings.Split(string(output), "\n")
+	var pids []string
+	for _, line := range lines {
+		line = strings.TrimSpace(line)
+		if line == "" || line == "ProcessId" {
+			continue
+		}
+
+		if _, err := strconv.Atoi(line); err == nil {
+			pids = append(pids, line)
+		}
+	}
+
+	for _, pidStr := range pids {
+		pid, err := strconv.Atoi(pidStr)
+		if err != nil {
+			continue
+		}
+
+		if pid == currentPID {
+			continue
+		}
+
+		cmd := exec.Command("taskkill", "/F", "/PID", pidStr)
+		if err := cmd.Run(); err != nil {
+			slog.Warn("failed to kill ollama process", "pid", pid, "err", err)
+		}
+	}
+
+	return nil
+}