kern: implement SvcGetProcessList

libraries/libmesosphere/include/mesosphere/kern_k_process.hpp

@@ -231,6 +231,9 @@ namespace ams::kern {
                 return this->cond_var.Wait(address, cv_key, tag, ns);
             }
 
+            static KProcess *GetProcessFromId(u64 process_id);
+            static Result GetProcessList(s32 *out_num_processes, ams::kern::svc::KUserPointer<u64 *> out_process_ids, s32 max_out_count);
+
             static void Switch(KProcess *cur_process, KProcess *next_process) {
                 /* Set the current process pointer. */
                 SetCurrentProcess(next_process);

libraries/libmesosphere/source/kern_k_process.cpp

@@ -455,4 +455,52 @@ namespace ams::kern {
         MESOSPHERE_UNIMPLEMENTED();
     }
 
+    KProcess *KProcess::GetProcessFromId(u64 process_id) {
+        /* Lock the list. */
+        ListAccessor accessor;
+        const auto end = accessor.end();
+
+        /* Iterate over the list. */
+        for (auto it = accessor.begin(); it != end; ++it) {
+            /* Get the process. */
+            KProcess *process = static_cast<KProcess *>(std::addressof(*it));
+
+            if (process->GetId() == process_id) {
+                if (AMS_LIKELY(process->Open())) {
+                    return process;
+                }
+            }
+        }
+
+        /* We failed to find the process. */
+        return nullptr;
+    }
+
+    Result KProcess::GetProcessList(s32 *out_num_processes, ams::kern::svc::KUserPointer<u64 *> out_process_ids, s32 max_out_count) {
+        /* Lock the list. */
+        ListAccessor accessor;
+        const auto end = accessor.end();
+
+        /* Iterate over the list. */
+        s32 count = 0;
+        for (auto it = accessor.begin(); it != end; ++it) {
+            /* If we're within array bounds, write the id. */
+            if (count < max_out_count) {
+                /* Get the process id. */
+                KProcess *process = static_cast<KProcess *>(std::addressof(*it));
+                const u64 id = process->GetId();
+
+                /* Copy the id to userland. */
+                R_TRY(out_process_ids.CopyArrayElementFrom(std::addressof(id), count));
+            }
+
+            /* Increment the count. */
+            ++count;
+        }
+
+        /* We successfully iterated the list. */
+        *out_num_processes = count;
+        return ResultSuccess();
+    }
+
 }

libraries/libmesosphere/source/svc/kern_svc_process.cpp

@@ -52,7 +52,18 @@ namespace ams::kern::svc {
             return ResultSuccess();
         }
 
+        Result GetProcessList(int32_t *out_num_processes, KUserPointer<uint64_t *> out_process_ids, int32_t max_out_count) {
+            /* Validate that the out count is valid. */
+            R_UNLESS((0 <= max_out_count && max_out_count <= static_cast<int32_t>(std::numeric_limits<int32_t>::max() / sizeof(u64))), svc::ResultOutOfRange());
 
+            /* Validate that the pointer is in range. */
+            if (max_out_count > 0) {
+                R_UNLESS(GetCurrentProcess().GetPageTable().Contains(KProcessAddress(out_process_ids.GetUnsafePointer()), max_out_count * sizeof(u64)), svc::ResultInvalidCurrentMemory());
+            }
+
+            /* Get the process list. */
+            return KProcess::GetProcessList(out_num_processes, out_process_ids, max_out_count);
+        }
 
     }
 
@@ -67,7 +78,7 @@ namespace ams::kern::svc {
     }
 
     Result GetProcessList64(int32_t *out_num_processes, KUserPointer<uint64_t *> out_process_ids, int32_t max_out_count) {
-        MESOSPHERE_PANIC("Stubbed SvcGetProcessList64 was called.");
+        return GetProcessList(out_num_processes, out_process_ids, max_out_count);
     }
 
     Result CreateProcess64(ams::svc::Handle *out_handle, KUserPointer<const ams::svc::lp64::CreateProcessParameter *> parameters, KUserPointer<const uint32_t *> caps, int32_t num_caps) {
@@ -97,7 +108,7 @@ namespace ams::kern::svc {
     }
 
     Result GetProcessList64From32(int32_t *out_num_processes, KUserPointer<uint64_t *> out_process_ids, int32_t max_out_count) {
-        MESOSPHERE_PANIC("Stubbed SvcGetProcessList64From32 was called.");
+        return GetProcessList(out_num_processes, out_process_ids, max_out_count);
     }
 
     Result CreateProcess64From32(ams::svc::Handle *out_handle, KUserPointer<const ams::svc::ilp32::CreateProcessParameter *> parameters, KUserPointer<const uint32_t *> caps, int32_t num_caps) {