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jasjivsingh-corpjasjivsingh-corp
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Fix fork safety in keysinuse by recreating locks
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‎DEBUG_SYMBOLS.md‎

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# Debug Symbols Guide for SymCrypt OpenSSL Provider
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## Understanding Debug Symbols
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### Symbol Types
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1. **No Symbols (Stripped)**
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- Binary has no function names or debug info
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- `file` output: "stripped"
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- GDB can't show function names or source code
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2. **Basic Symbols**
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- Has function names in `.symtab` section
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- `file` output: "not stripped"
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- GDB can set breakpoints by function name
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- ❌ No source code viewing
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- ❌ No variable inspection
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- ❌ No line-by-line stepping
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3. **Debug Symbols (DWARF)**
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- Has `.debug_*` sections
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- Includes source file/line mapping
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- ✅ Full source code viewing in GDB
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- ✅ Variable inspection
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- ✅ Line-by-line stepping
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- ✅ Type information
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## How to Add Debug Symbols
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### Method 1: Use CMAKE_BUILD_TYPE (Recommended)
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```bash
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# Clean rebuild with debug symbols
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cd /home/jasjivsingh/SymCrypt-OpenSSL
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./build_debug.sh
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```
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Or manually:
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```bash
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cd /home/jasjivsingh/SymCrypt-OpenSSL/build
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cmake -DCMAKE_BUILD_TYPE=Debug ..
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make -j$(nproc)
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```
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**Build Types:**
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- `Debug`: `-g3 -O0` (no optimization, max debug info)
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- `RelWithDebInfo`: `-g -O2` (optimized + debug symbols)
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- `Release`: `-O3` (optimized, no debug by default)
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### Method 2: Add Debug Flags Manually
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```bash
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cd /home/jasjivsingh/SymCrypt-OpenSSL/build
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cmake -DCMAKE_C_FLAGS="-g3" -DCMAKE_CXX_FLAGS="-g3" ..
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make -j$(nproc)
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```
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### Method 3: Modify CMakeLists.txt
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Already done! The file now has:
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```cmake
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set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} -g3 -O0 -DDEBUG")
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set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -g3 -O0 -DDEBUG")
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```
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## Debug Flag Options
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| Flag | Description |
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|------|-------------|
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| `-g` | Include basic debug information |
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| `-g3` | Include macro definitions and extra debug info |
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| `-ggdb` | Generate debug info for GDB specifically |
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| `-O0` | No optimization (easier to debug) |
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| `-O2` | Optimize (harder to debug, variables optimized away) |
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| `-fno-omit-frame-pointer` | Keep frame pointer (better backtraces) |
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## Verify Debug Symbols
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### Check if symbols exist:
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```bash
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file symcryptprovider.so
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# Should say: "not stripped"
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```
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### Check for debug sections:
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```bash
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objdump -h symcryptprovider.so | grep debug
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# Should show: .debug_info, .debug_line, .debug_str, etc.
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```
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### Check symbol table:
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```bash
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nm -D symcryptprovider.so | grep scossl_provider_init
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# Should show: function symbols
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```
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### Detailed debug info:
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```bash
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readelf -w symcryptprovider.so | head -100
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# Shows DWARF debug information
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```
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## Using Debug Symbols in GDB
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### Load Symbols
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```gdb
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# GDB should auto-load symbols when attaching
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# If not, manually load:
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sharedlibrary symcryptprovider
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# Check if loaded:
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info sharedlibrary symcrypt
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```
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### Set Source Directories
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```gdb
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# Tell GDB where source files are:
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directory /home/jasjivsingh/SymCrypt-OpenSSL/SymCryptProvider/src
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directory /home/jasjivsingh/SymCrypt-OpenSSL/ScosslCommon/src
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```
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### Verify Symbols Loaded
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```gdb
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# List functions:
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info functions scossl_
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# Show source for a function:
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list scossl_provider_init
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# Check debug info:
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maint info symtabs
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```
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## Troubleshooting Symbol Loading
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### Problem: GDB says "No debugging symbols found"
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**Solution 1:** Check if debug symbols exist
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```bash
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objdump -h /usr/lib/x86_64-linux-gnu/ossl-modules/symcryptprovider.so | grep debug
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```
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**Solution 2:** Rebuild with debug symbols
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```bash
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./build_debug.sh
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```
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**Solution 3:** Point GDB to build directory
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```gdb
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set debug-file-directory /home/jasjivsingh/SymCrypt-OpenSSL/build
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```
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### Problem: "No source file named ..."
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**Solution:** Add source directories
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```gdb
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directory /home/jasjivsingh/SymCrypt-OpenSSL/SymCryptProvider/src
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```
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### Problem: Variables show "<optimized out>"
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**Cause:** Code was compiled with optimization (`-O2`, `-O3`)
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**Solution:** Use Debug build type (`-O0`)
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```bash
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cmake -DCMAKE_BUILD_TYPE=Debug ..
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```
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## Best Practices
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### For Development/Debugging
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```bash
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cmake -DCMAKE_BUILD_TYPE=Debug ..
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# Pros: Full debug info, no optimization
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# Cons: Slower execution
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```
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### For Production Debugging
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```bash
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cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo ..
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# Pros: Optimized + debug symbols
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# Cons: Some variables optimized away
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```
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### For Production Release
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```bash
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cmake -DCMAKE_BUILD_TYPE=Release ..
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# Then optionally strip:
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strip --strip-debug symcryptprovider.so
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```
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## Quick Reference
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| Task | Command |
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|------|---------|
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| Build with debug | `./build_debug.sh` |
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| Check for debug symbols | `objdump -h *.so \| grep debug` |
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| Check if stripped | `file *.so` |
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| List symbols | `nm -D *.so` |
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| Debug with GDB | `./debug_nginx_provider.sh attach` |
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## File Sizes Comparison
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Typical sizes for the provider:
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- **Stripped Release**: ~500KB
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- **Release with symbols**: ~1MB
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- **Debug**: ~2-3MB (includes debug sections)
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The debug sections add overhead but provide invaluable debugging capability.

‎DIAGRAMS.md‎

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sequenceDiagram
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autonumber
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participant Parent
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participant System
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participant Child
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Note over Parent: Normal Execution
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Parent->>Parent: keysinuse_atfork_prepare()
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Parent->>Parent: LOCK EVERYTHING (Mutex + RWLocks)
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Parent->>System: fork()
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System->>Child: Copy Memory (Locks are LOCKED)
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par Parent Resume
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Parent->>Parent: keysinuse_atfork_parent()
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Parent->>Parent: UNLOCK EVERYTHING
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Note over Parent: Continues...
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and Child Resume
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Child->>Child: keysinuse_atfork_child()
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Note right of Child: Cannot unlock RWLocks (Wrong Owner)
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Child->>Child: DESTROY Old RWLocks
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Child->>Child: CREATE New RWLocks
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Child->>Child: UNLOCK Mutex
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Child->>Child: Start New Logging Thread
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sequenceDiagram
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autonumber
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participant Parent
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participant System
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participant Child
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Note over Parent: Normal Execution
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Parent->>Parent: keysinuse_atfork_prepare()
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Parent->>Parent: LOCK EVERYTHING (Mutex + RWLocks)
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Parent->>System: fork()
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System->>Child: Copy Memory (Locks are LOCKED)
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par Parent Resume
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Parent->>Parent: keysinuse_atfork_parent()
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Parent->>Parent: UNLOCK EVERYTHING
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Note over Parent: Continues...
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and Child Resume
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Child->>Child: keysinuse_atfork_child()
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Note right of Child: Cannot unlock RWLocks (Wrong Owner)
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Child->>Child: DESTROY Old RWLocks
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Child->>Child: CREATE New RWLocks
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Child->>Child: UNLOCK Mutex
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Child->>Child: Start New Logging Thread
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end

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