[PATCH v2 0/2] MR3658: mmdevapi: Simplify load_driver_devices() by combining loops and removing unneeded allocation(s), move name string duplication in MMDevice_Create() from caller.

[Davide Beatrici (＠davidebeatrici)]

--
  v2: mmdevapi: Move name string duplication in MMDevice_Create() from caller.
      mmdevapi: Simplify load_driver_devices() by combining loops and removing unneeded allocation(s).

https://gitlab.winehq.org/wine/wine/-/merge_requests/3658

[PATCH v2 1/2] mmdevapi: Simplify load_driver_devices() by combining loops and removing unneeded allocation(s).

[Davide Beatrici]

From: Davide Beatrici

---
 dlls/mmdevapi/devenum.c | 28 ++++++++--------------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/dlls/mmdevapi/devenum.c b/dlls/mmdevapi/devenum.c
index 2900d222795..f93bfa83ec7 100644
--- a/dlls/mmdevapi/devenum.c
+++ b/dlls/mmdevapi/devenum.c
@@ -528,8 +528,6 @@ static HRESULT set_format(MMDevice *dev)
 HRESULT load_driver_devices(EDataFlow flow)
 {
     struct get_endpoint_ids_params params;
-    WCHAR **ids = NULL;
-    GUID *guids = NULL;
     UINT i;

params.flow = flow;
@@ -544,38 +542,28 @@ HRESULT load_driver_devices(EDataFlow flow)
     if (FAILED(params.result))
         goto end;

-    ids = malloc(params.num * sizeof(*ids));
-    guids = malloc(params.num * sizeof(*guids));
-    if (!ids || !guids) {
-        params.result = E_OUTOFMEMORY;
-        goto end;
-    }
-
     for (i = 0; i < params.num; i++) {
+        GUID guid;
+        WCHAR *id;
+        MMDevice *dev;
         const WCHAR *name = (WCHAR *)((char *)params.endpoints + params.endpoints[i].name);
         const char *dev_name = (char *)params.endpoints + params.endpoints[i].device;
         const unsigned int size = (wcslen(name) + 1) * sizeof(WCHAR);

-        if (!(ids[i] = malloc(size))) {
-            while (i--) free(ids[i]);
+        if (!(id = malloc(size))) {
             params.result = E_OUTOFMEMORY;
             goto end;
         }
-        memcpy(ids[i], name, size);
-        drvs.pget_device_guid(flow, dev_name, &guids[i]);
-    }
+        memcpy(id, name, size);

-    for (i = 0; i < params.num; i++) {
-        MMDevice *dev;
-        dev = MMDevice_Create(ids[i], &guids[i], flow, DEVICE_STATE_ACTIVE,
-                params.default_idx == i);
+        drvs.pget_device_guid(flow, dev_name, &guid);
+
+        dev = MMDevice_Create(id, &guid, flow, DEVICE_STATE_ACTIVE, params.default_idx == i);
         set_format(dev);
     }

end:
     free(params.endpoints);
-    free(guids);
-    free(ids);

return params.result;
 }

[PATCH v2 2/2] mmdevapi: Move name string duplication in MMDevice_Create() from caller.

[Davide Beatrici]

From: Davide Beatrici

---
 dlls/mmdevapi/devenum.c | 21 +++++----------------
 1 file changed, 5 insertions(+), 16 deletions(-)

diff --git a/dlls/mmdevapi/devenum.c b/dlls/mmdevapi/devenum.c
index f93bfa83ec7..10037a7affe 100644
--- a/dlls/mmdevapi/devenum.c
+++ b/dlls/mmdevapi/devenum.c
@@ -312,7 +312,7 @@ static const WCHAR *find_product_name_override(const WCHAR *device_id)
  * If GUID is null, a random guid will be assigned
  * and the device will be created
  */
-static MMDevice *MMDevice_Create(WCHAR *name, GUID *id, EDataFlow flow, DWORD state, BOOL setdefault)
+static MMDevice *MMDevice_Create(const WCHAR *name, GUID *id, EDataFlow flow, DWORD state, BOOL setdefault)
 {
     HKEY key, root;
     MMDevice *device, *cur = NULL;
@@ -351,7 +351,7 @@ static MMDevice *MMDevice_Create(WCHAR *name, GUID *id, EDataFlow flow, DWORD st
         WARN("Modifying an MMDevice with postitive reference count!\n");

free(cur->drv_id);
-    cur->drv_id = name;
+    cur->drv_id = wcsdup(name);

cur->flow = flow;
     cur->state = state;
@@ -373,7 +373,7 @@ static MMDevice *MMDevice_Create(WCHAR *name, GUID *id, EDataFlow flow, DWORD st
             PROPVARIANT pv;

pv.vt = VT_LPWSTR;
-            pv.pwszVal = name;
+            pv.pwszVal = cur->drv_id;

if (SUCCEEDED(set_driver_prop_value(id, flow, &devicepath_key))) {
                 PROPVARIANT pv2;
@@ -482,10 +482,7 @@ HRESULT load_devices_from_reg(void)
             && SUCCEEDED(MMDevice_GetPropValue(&guid, curflow, (const PROPERTYKEY*)&DEVPKEY_Device_FriendlyName, &pv))
             && pv.vt == VT_LPWSTR)
         {
-            DWORD size_bytes = (lstrlenW(pv.pwszVal) + 1) * sizeof(WCHAR);
-            WCHAR *name = malloc(size_bytes);
-            memcpy(name, pv.pwszVal, size_bytes);
-            MMDevice_Create(name, &guid, curflow,
+            MMDevice_Create(pv.pwszVal, &guid, curflow,
                     DEVICE_STATE_NOTPRESENT, FALSE);
             CoTaskMemFree(pv.pwszVal);
         }
@@ -544,21 +541,13 @@ HRESULT load_driver_devices(EDataFlow flow)

for (i = 0; i < params.num; i++) {
         GUID guid;
-        WCHAR *id;
         MMDevice *dev;
         const WCHAR *name = (WCHAR *)((char *)params.endpoints + params.endpoints[i].name);
         const char *dev_name = (char *)params.endpoints + params.endpoints[i].device;
-        const unsigned int size = (wcslen(name) + 1) * sizeof(WCHAR);
-
-        if (!(id = malloc(size))) {
-            params.result = E_OUTOFMEMORY;
-            goto end;
-        }
-        memcpy(id, name, size);

drvs.pget_device_guid(flow, dev_name, &guid);

-        dev = MMDevice_Create(id, &guid, flow, DEVICE_STATE_ACTIVE, params.default_idx == i);
+        dev = MMDevice_Create(name, &guid, flow, DEVICE_STATE_ACTIVE, params.default_idx == i);
         set_format(dev);
     }

[Davide Beatrici (＠davidebeatrici)]

On Wed Aug 30 00:17:34 2023 +0000, Huw Davies wrote:
> Could we add a second commit to this MR that moves the duplication of
> the `name` parameter to `MMDevice_Create()`? (using `wcsdup()` for that
> would be good too).

Done.

[PATCH v2 0/2] MR3658: mmdevapi: Simplify load_driver_devices() by combining loops and removing unneeded allocation(s), move name string duplication in MMDevice_Create() from caller. - approved

[Huw Davies (＠huw)]

This merge request was approved by Huw Davies.