Fix how chunk servers handle state updates from the metadata server
based on the design in DESIGN.txt. The implementation now:
1. Checks if chunks in the add_list exist in the chunk store and
collects any missing chunks
2. Unmarks chunks in the add_list that were previously marked for removal
3. Marks chunks in the rem_list for removal with timestamps
4. Responds with SUCCESS if all chunks are present, or ERROR with the
list of missing chunks
Added:
- RemovalList data structure to track chunks marked for deletion with
timestamps
- chunk_store_exists() to check if a chunk file exists
- Helper functions for removal list management (init, free, add, remove, find)
This implements the garbage collection mechanism described in DESIGN.txt
where chunks are marked for removal and can be unmarked if they appear
in the add_list again.
Unified the function signatures across all process types (metadata server,
chunk server, and simulation client) to accept an int *timeout parameter.
This provides consistency in the simulation framework and allows all
process types to control their wakeup times.
**Changes:**
**Headers (metadata_server.h, chunk_server.h):**
- Updated metadata_server_init() to accept int *timeout parameter
- Updated metadata_server_step() to accept int *timeout parameter
- Updated chunk_server_init() to accept int *timeout parameter
- Updated chunk_server_step() to accept int *timeout parameter
**Implementations (metadata_server.c, chunk_server.c):**
- Modified init functions to set *timeout = -1 (no timeout needed)
- Modified step functions to set *timeout = -1 (no timeout needed)
- Both server types currently don't require periodic wakeups, but the
parameter allows for future timeout-based behavior
**System Integration (system.c):**
- Updated spawn_simulated_process() to declare timeout variable once
and pass it to all process init functions uniformly
- Updated update_simulation() to declare timeout variable once and
pass it to all process step functions uniformly
- Simplified control flow by removing special case for client timeout
handling - now all process types use the same timeout logic
- Consolidated timeout-to-wakeup_time conversion after switch statements
**Benefits:**
- Consistent API across all process types
- Cleaner code with reduced duplication
- Future-proof for server timeout requirements
- All processes now managed uniformly by simulation framework
The simulation continues to run correctly with all process types
handling timeout parameter appropriately.