Refactor duplicated code across kernel subsystems

[Copilot]

Eliminates ~45 lines of duplicated logic across command handling, memory management, and I/O subsystems.

Changes

Command dispatch - Replaced if-else strcmp chains with table-driven lookup:

// Before: 6 repetitive if-else blocks
if (strcmp(command, "ping") == 0) cmd_ping();
else if (strcmp(command, "crash") == 0) cmd_crash();
// ...

// After: Extensible command table
static const command_t commands[] = {
    {"ping", cmd_ping}, {"crash", cmd_crash}, ...
};

Printf base conversion - putnbr_base() now delegates to putnbr_base_unsigned() after sign handling, eliminating 10 lines of recursive duplication

Page table access - Extracted get_page_table() to remove repeated recursive_active() checks across map_page(), unmap_page(), and get_phys_addr()

PIC IRQ masking - Unified pic_enable_irq() and pic_disable_irq() via pic_set_irq_mask(bool enable) helper

Bug fix - Corrected get_level() in printk.c: c >= '0' || c <= '7' → c >= '0' && c <= '7'

Stats

• 7 files changed: +52, -58 lines
• Duplication eliminated: ~45 lines
• Command system now table-driven for easier extensibility

Original prompt

Find and refactor duplicated code

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[Copilot]

Pull Request Overview

This PR contains several refactoring improvements and bug fixes across the kernel codebase, focusing on code deduplication, fixing logical errors, and improving maintainability.

• Fixed a critical logical operator bug in get_level() that prevented proper level parsing
• Refactored duplicated code in PIC IRQ mask operations and paging table lookups into helper functions
• Improved command handling architecture by replacing if-else chains with a table-driven approach

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
kernel/src/tty/vprintf.c	Simplified putnbr_base() to delegate to putnbr_base_unsigned() after handling negative sign
kernel/src/tty/printk.c	Fixed logical OR to AND in get_level() condition
kernel/src/pic.c	Refactored pic_enable_irq() and pic_disable_irq() to share common logic via pic_set_irq_mask()
kernel/src/memory/paging.c	Extracted duplicated page table lookup logic into get_page_table() helper function
kernel/src/command/handle.c	Refactored command dispatch from if-else chain to table-driven approach
kernel/src/command/halt.c	Extracted halt command implementation into dedicated file
kernel/include/command.h	Added cmd_halt() function declaration

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud