chore(build): Use Purego with stablediffusion backend

Signed-off-by: Richard Palethorpe <[email protected]>

Author: richiejp

backend/go/stablediffusion-ggml/CMakeLists.txt

@@ -1,10 +1,11 @@
 cmake_minimum_required(VERSION 3.12)
 project(gosd LANGUAGES C CXX)
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
 add_subdirectory(./sources/stablediffusion-ggml.cpp)
 
 add_library(gosd MODULE gosd.cpp)
-target_link_libraries(gosd PRIVATE stable-diffusion ggml zip stdc++fs)
+target_link_libraries(gosd PRIVATE stable-diffusion ggml stdc++fs)
 
 target_include_directories(gosd PUBLIC
     stable-diffusion.cpp

backend/go/stablediffusion-ggml/gosd.cpp

@@ -90,7 +90,7 @@ static void sd_log_cb(enum sd_log_level_t level, const char* log, void* data) {
 }
 
 int load_model(const char *model, char *model_path, char* options[], int threads, int diff) {
-    fprintf (stderr, "Loading model!\n");
+    fprintf (stderr, "Loading model: %p=%s\n", model, model);
 
     sd_set_log_callback(sd_log_cb, NULL);
 
@@ -110,7 +110,7 @@ int load_model(const char *model, char *model_path, char* options[], int threads
     char *lora_dir = model_path;
     bool lora_dir_allocated = false;
 
-    fprintf(stderr, "parsing options\n");
+    fprintf(stderr, "parsing options: %p\n", options);
 
     // If options is not NULL, parse options
     for (int i = 0; options[i] != NULL; i++) {

backend/go/stablediffusion-ggml/gosd.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"unsafe"
 
@@ -20,10 +21,25 @@ type SDGGML struct {
 }
 
 var (
-	LoadModel func(model, model_apth string, options []string, threads int32, diff int) int
-	GenImage func(text, negativeText string, width, height, steps int, seed int64, dst string, cfgScale float32, srcImage string, strength float32, maskImage string, refImages []string, refImagesCount int) int
+	LoadModel func(model, model_apth string, options []uintptr, threads int32, diff int) int
+	GenImage  func(text, negativeText string, width, height, steps int, seed int64, dst string, cfgScale float32, srcImage string, strength float32, maskImage string, refImages []string, refImagesCount int) int
 )
 
+// Copied from Purego internal/strings
+// TODO: We should upstream sending []string
+func hasSuffix(s, suffix string) bool {
+	return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
+}
+
+func CString(name string) *byte {
+	if hasSuffix(name, "\x00") {
+		return &(*(*[]byte)(unsafe.Pointer(&name)))[0]
+	}
+	b := make([]byte, len(name)+1)
+	copy(b, name)
+	return &b[0]
+}
+
 func (sd *SDGGML) Load(opts *pb.ModelOptions) error {
 
 	sd.threads = int(opts.Threads)
@@ -56,8 +72,14 @@ func (sd *SDGGML) Load(opts *pb.ModelOptions) error {
 
 	fmt.Fprintf(os.Stderr, "Options: %+v\n", oo)
 
-	options := make([]string, len(oo), len(oo) + 1)
-	*(*uintptr)(unsafe.Add(unsafe.Pointer(&options), uintptr(len(oo)))) = 0
+	// At the time of writing Purego doesn't recurse into slices and convert Go strings to pointers so we need to do that
+	var keepAlive []any
+	options := make([]uintptr, len(oo), len(oo)+1)
+	for i, op := range oo {
+		bytep := CString(op)
+		options[i] = uintptr(unsafe.Pointer(bytep))
+		keepAlive = append(keepAlive, bytep)
+	}
 
 	sd.cfgScale = opts.CFGScale
 
@@ -66,6 +88,8 @@ func (sd *SDGGML) Load(opts *pb.ModelOptions) error {
 		return fmt.Errorf("could not load model")
 	}
 
+	runtime.KeepAlive(keepAlive)
+
 	return nil
 }
 
@@ -89,7 +113,7 @@ func (sd *SDGGML) GenerateImage(opts *pb.GenerateImageRequest) error {
 	}
 
 	refImagesCount := len(opts.RefImages)
-	refImages := make([]string, refImagesCount, refImagesCount + 1)
+	refImages := make([]string, refImagesCount, refImagesCount+1)
 	copy(refImages, opts.RefImages)
 	*(*uintptr)(unsafe.Add(unsafe.Pointer(&refImages), refImagesCount)) = 0
 

backend/go/stablediffusion-ggml/package.sh

@@ -10,6 +10,7 @@ CURDIR=$(dirname "$(realpath $0)")
 # Create lib directory
 mkdir -p $CURDIR/package/lib
 
+cp -avrf $CURDIR/libgosd.so $CURDIR/package/
 cp -avrf $CURDIR/stablediffusion-ggml $CURDIR/package/
 cp -rfv $CURDIR/run.sh $CURDIR/package/
 
@@ -47,6 +48,6 @@ else
     exit 1
 fi
 
-echo "Packaging completed successfully" 
+echo "Packaging completed successfully"
 ls -liah $CURDIR/package/
-ls -liah $CURDIR/package/lib/
+ls -liah $CURDIR/package/lib/