Add fake-memory-reader tests for the scanner/poller

process.go's boundary functions (readMemory, findModuleBase,
productVersion, findProcessID, openProcess, closeProcessHandle) become
swappable package variables, same pattern as testExeDir in totals.go.
process_test.go builds a fakeProcess (an in-memory buffer addressed
like real process memory) to exercise signature scanning, scanModule's
chunk-overlap logic, PlayerIns confirmation by memory read (the path
Linux always takes), the save-slot read, the double-read name
confirmation rule, and rejection of raw-pointer-as-UTF16 garbage.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

process.go

@@ -31,6 +31,19 @@ const processName = "eldenring.exe"
 // process_linux.go).
 type procHandle uintptr
 
+// Boundary functions as package variables, defaulting to the platform
+// implementation compiled into process_windows.go/process_linux.go.
+// Tests (process_test.go) swap these for a fake in-memory reader — same
+// pattern as testExeDir in totals.go, not a new interface.
+var (
+	findProcessIDFn      = findProcessID
+	openProcessFn        = openProcess
+	closeProcessHandleFn = closeProcessHandle
+	readMemoryFn         = readMemory
+	findModuleBaseFn     = findModuleBase
+	productVersionFn     = productVersion
+)
+
 // ------------------------- signature scans -------------------------
 //
 // Two signatures, both the same shape: a 7-byte "mov reg,[rip+disp32]"
@@ -111,7 +124,7 @@ func scanModule(h procHandle, base uintptr, size uint32, patterns [][]patByte) [
 		if rem := int(size - pos); readSize > rem {
 			readSize = rem
 		}
-		buf, ok := readMemory(h, base+uintptr(pos), readSize)
+		buf, ok := readMemoryFn(h, base+uintptr(pos), readSize)
 		if ok {
 			for i := 0; i < len(buf); i++ {
 				for p := range patterns {
@@ -140,7 +153,7 @@ func ripSlot(h procHandle, matchAddr uintptr) (uintptr, error) {
 		return 0, fmt.Errorf("pattern not found")
 	}
 	codeLocation := matchAddr + 3 // the first 3 bytes are the opcode
-	dispBytes, ok := readMemory(h, codeLocation, 4)
+	dispBytes, ok := readMemoryFn(h, codeLocation, 4)
 	if !ok {
 		return 0, fmt.Errorf("couldn't read the RIP-relative displacement")
 	}
@@ -178,12 +191,12 @@ type gamePointers struct {
 func resolvePointers(h procHandle, pid uint32) (gamePointers, error) {
 	var gp gamePointers
 
-	base, size, exePath, err := findModuleBase(pid, processName)
+	base, size, exePath, err := findModuleBaseFn(pid, processName)
 	if err != nil {
 		return gp, err
 	}
 
-	major, minor, label, okVer := productVersion(exePath)
+	major, minor, label, okVer := productVersionFn(exePath)
 	gp.playerInsTried = playerInsCandidates(major, minor, okVer)
 	gp.playerInsOffset = gp.playerInsTried[0]
 	gp.versionLabel = label
@@ -216,7 +229,7 @@ func derefPointer(h procHandle, slot uintptr) (uintptr, bool) {
 	if slot == 0 {
 		return 0, false
 	}
-	buf, ok := readMemory(h, slot, 8)
+	buf, ok := readMemoryFn(h, slot, 8)
 	if !ok {
 		return 0, false
 	}
@@ -257,7 +270,7 @@ func readCharName(h procHandle, gameDataMan uintptr, c nameCandidate) (string, b
 		}
 		base = p
 	}
-	buf, ok := readMemory(h, base+c.nameOffset, charNameMaxChars*2)
+	buf, ok := readMemoryFn(h, base+c.nameOffset, charNameMaxChars*2)
 	if !ok {
 		return "", false
 	}
@@ -316,7 +329,7 @@ func readSaveSlot(h procHandle, gp gamePointers) int {
 	if !ok || gameMan == 0 {
 		return -1
 	}
-	buf, ok := readMemory(h, gameMan+saveSlotOffset, 1)
+	buf, ok := readMemoryFn(h, gameMan+saveSlotOffset, 1)
 	if !ok {
 		return -1
 	}
@@ -365,7 +378,7 @@ func isPlayerLoaded(h procHandle, gp *gamePointers) (loaded bool, known bool) {
 		}
 		// A real pointer points at mapped memory; a garbage one almost
 		// never survives this read.
-		if _, ok := readMemory(h, playerIns, 8); !ok {
+		if _, ok := readMemoryFn(h, playerIns, 8); !ok {
 			continue
 		}
 		gp.playerInsOffset = cand
@@ -436,7 +449,7 @@ func pollLoop() {
 
 	closeHandle := func() {
 		if handle != 0 {
-			closeProcessHandle(handle)
+			closeProcessHandleFn(handle)
 			handle = 0
 		}
 		pid = 0
@@ -449,13 +462,13 @@ func pollLoop() {
 
 	for {
 		if handle == 0 {
-			newPid, err := findProcessID(processName)
+			newPid, err := findProcessIDFn(processName)
 			if err != nil {
 				st.setDisconnected("waiting for eldenring.exe")
 				time.Sleep(3 * time.Second)
 				continue
 			}
-			h, err := openProcess(newPid)
+			h, err := openProcessFn(newPid)
 			if err != nil {
 				st.setDisconnected("couldn't open the process (permissions?): " + err.Error())
 				time.Sleep(3 * time.Second)
@@ -472,7 +485,7 @@ func pollLoop() {
 				st.setDisconnected(err.Error())
 				time.Sleep(2 * time.Second)
 				// if the process died, release the handle to retry from scratch
-				if _, ferr := findProcessID(processName); ferr != nil {
+				if _, ferr := findProcessIDFn(processName); ferr != nil {
 					closeHandle()
 				}
 				continue
@@ -510,7 +523,7 @@ func pollLoop() {
 			// and our detection was lying. Unlike a timeout, this can't
 			// fire just from leaving the game sitting at the menu a while.
 			if gdm, ok := derefPointer(handle, gp.gameDataManSlot); ok && gdm != 0 {
-				if buf, ok := readMemory(handle, gdm+0x94, 4); ok {
+				if buf, ok := readMemoryFn(handle, gdm+0x94, 4); ok {
 					raw := int32(binary.LittleEndian.Uint32(buf))
 					if raw >= 0 && raw < 1_000_000 {
 						if haveUnloadedRaw {
@@ -562,8 +575,8 @@ func pollLoop() {
 			continue
 		}
 
-		deathsBuf, ok1 := readMemory(handle, gameDataMan+0x94, 4)
-		bossBuf, ok2 := readMemory(handle, gameDataMan+0xC0, 1)
+		deathsBuf, ok1 := readMemoryFn(handle, gameDataMan+0x94, 4)
+		bossBuf, ok2 := readMemoryFn(handle, gameDataMan+0xC0, 1)
 		if !ok1 {
 			st.setDisconnected("lost the memory reading (the game closed or restarted)")
 			closeHandle()