find-cbaseentity-emitsoundparams

name	find-CBaseEntity_EmitSoundParams
description	Find and identify the CBaseEntity_EmitSoundParams function in CS2 binary using IDA Pro MCP. Use this skill when reverse engineering CS2 server.dll or server.so to locate the EmitSoundParams function by searching for the "Stops a named sound playing from this" string, tracing xrefs, and identifying the function via a volume-check code pattern.

Find CBaseEntity_EmitSoundParams

Locate CBaseEntity_EmitSoundParams in CS2 server.dll or server.so using IDA Pro MCP tools.

Method

1. Search for the string:

   mcp__ida-pro-mcp__find_regex pattern="Stops a named sound playing from this"
   

2. Get cross-references to the string:

   mcp__ida-pro-mcp__xrefs_to addrs="<string_addr>"
   

3. Disassemble around the xref address (*DO NOT decompile the whole referencing function — it is too large):

   mcp__ida-pro-mcp__disasm addr="<xref_addr - 0x60>" max_instructions=40
   

4. In the disassembly before lea REG, aStopsANamedSou, find the last two lea REG, sub_XXXXXXX instructions. These reference two candidate functions.

5. Decompile both candidate functions and look for the volume-check pattern:

   if ( a3 != 100 && a3 > 0 )
     v19 = a3;
   

   or equivalent:

   if ( a3 != 100 )
   {
     if ( a3 > 0 )
       v5 = a3;
     v15 = v5;
   }
   

   The function containing this pattern is CBaseEntity_EmitSoundParams.

6. Rename the function:

   mcp__ida-pro-mcp__rename batch={"func": [{"addr": "<function_addr>", "name": "CBaseEntity_EmitSoundParams"}]}
   

7. Generate and validate unique signature:

   ALWAYS Use SKILL /generate-signature-for-function to generate a robust and unique signature for CBaseEntity_EmitSoundParams.

8. Write IDA analysis output as YAML beside the binary:

   ALWAYS Use SKILL /write-func-as-yaml to write the analysis results.

   Required parameters:

   • func_name: CBaseEntity_EmitSoundParams
   • func_addr: The function address from step 5
   • func_sig: The validated signature from step 7

Function Characteristics

• Parameters: (this, sound_name, volume, pitch, delay) where this is CBaseEntity pointer
• Volume default: 100 — overridden by a3 when a3 != 100 && a3 > 0
• Not a virtual function — use /write-func-as-yaml (not vfunc variant)

Output YAML Format

The output YAML filename depends on the platform:

• server.dll → CBaseEntity_EmitSoundParams.windows.yaml
• server.so → CBaseEntity_EmitSoundParams.linux.yaml