update shell, add free command, improve libc

Author: alexeev-prog

CHANGELOG.md

@@ -1,3 +1,9 @@
+commit 0867ca069cf902e68c0ef2e5e605c32d2d0cabcc
+Author: Alexeev Bronislav <alexeev.dev@mail.ru>
+Date:   Fri Aug 22 22:24:39 2025 +0700
+
+    improve info command, improve memory system
+
 commit 0176c2367607690e3198f7dccac0a1d26521e82d
 Author: Alexeev Bronislav <alexeev.dev@mail.ru>
 Date:   Fri Aug 22 22:03:20 2025 +0700

src/kernel/kernel/kernel.c

@@ -56,16 +56,18 @@ char** get_args(char *input) {
 void user_input(char *input) {
 	// Массив структур команд, состоящий из самой команды, подсказки и указателя до void-функции
 	struct { char *text, *hint; void (*command)(char**); } commands[] = {
-		//   Команда            		Подсказка для команды                   Указатель до функции
+		//   Команда            		Подсказка для команды                  	 					Указатель до функции
 		{.text="END",		   		.hint="HALT CPU", 											.command=&halt_cpu},
 		{.text="CLEAR", 	   		.hint="Clear screen",										.command=&clear_screen_command},
 		{.text="AMALLOC", 		   	.hint="Kernel Arena Malloc. Usage: AMALLOC <size>",			.command=&arena_malloc_command_shell},
 		{.text="QEMUSHUTDOWN",		.hint="Shutdown QEMU",										.command=&shutdown_qemu},
 		{.text="INFO",				.hint="Get info",											.command=&info_command_shell},
 		{.text="FREEMEMADDR",		.hint="Get free mem addr",									.command=&print_freememaddr},
 		{.text="TESTMEM", 			.hint="Test memory",										.command=&test_mem_command},
-		{.text="KMEMDUMP", 			.hint="Dump memory",										.command=&mem_dump},
-		{.text="KMALLOC",			.hint="Alloc memory. Usage: KMALLOC <size>",				.command=&kmalloc_command}
+		{.text="MEMDUMP", 			.hint="Dump memory",										.command=&mem_dump},
+		{.text="MALLOC",			.hint="Alloc memory. Usage: MALLOC <size>",					.command=&kmalloc_command},
+		{.text="FREE",				.hint="Free memory. Usage: FREE <address>",					.command=&free_command},
+		{.text="ECHO",				.hint="Echo an text",										.command=&echo_command}
 	};
 
 	int executed = 0;

src/kernel/kernel/utils.c

@@ -73,9 +73,32 @@ void mem_dump(char** args) {
 	kmemdump();
 }
 
+void echo_command(char **args) {
+    for (int i = 0; args[i] != NULL; i++) {
+        kprintf("%s ", args[i]);
+    }
+    kprint("\n");
+}
+
+void free_command(char **args) {
+    if (!args[0]) {
+        kprint("FREE usage: FREE <hex_address>\n");
+        return;
+    }
+
+    char *addr_str = args[0];
+    if (addr_str[0] == '0' && addr_str[1] == 'x') {
+        addr_str += 2;
+    }
+
+    u32 addr = hex_strtoint(addr_str);
+    kfree((void*)addr);
+    kprintf("Freed memory at %x\n", addr);
+}
+
 void kmalloc_command(char** args) {
 	if (args[0] == NULL) {
-		kprint("KMALLOC usage: KMALLOC <bytes>");
+		kprint("MALLOC usage: MALLOC <bytes>");
 		return;
 	}
 

src/kernel/kernel/utils.h

@@ -12,5 +12,7 @@ void test_mem_command(char** args);
 void mem_dump(char** args);
 void clear_screen_command(char** args);
 void kmalloc_command(char** args);
+void echo_command(char** args);
+void free_command(char **args);
 
 #endif

src/kernel/libc/mem.c

@@ -43,6 +43,20 @@ void heap_init() {
     kprint("\n");
 }
 
+// TODO: Paging is not implemented
+void *get_physaddr(void *virtualaddr) {
+    unsigned long pdindex = (unsigned long)virtualaddr >> 22;
+    unsigned long ptindex = (unsigned long)virtualaddr >> 12 & 0x03FF;
+
+    unsigned long *pd = (unsigned long *)0xFFFFF000;
+    // Here you need to check whether the PD entry is present.
+
+    unsigned long *pt = ((unsigned long *)0xFFC00000) + (0x400 * pdindex);
+    // Here you need to check whether the PT entry is present.
+
+    return (void *)((pt[ptindex] & ~0xFFF) + ((unsigned long)virtualaddr & 0xFFF));
+}
+
 void* kmalloc_new(u32 size) {
     // Выравниваем размер до границы BLOCK_SIZE
     if (size % BLOCK_SIZE != 0) {
@@ -76,13 +90,13 @@ void* kmalloc_new(u32 size) {
     }
 
     kprint("No free blocks found\n");
-    return NULL; // Не нашли свободного блока
+    return NULL;
 }
 
 void kfree(void* ptr) {
     if (!ptr) return;
 
-    // Получаем указатель на заголовок блока
+    // получаем указатель на заголовок блока
     mem_block_t* block = (mem_block_t*)((u32)ptr - sizeof(mem_block_t));
 
     if (block->is_free) { // блок уже освобожден
@@ -92,13 +106,14 @@ void kfree(void* ptr) {
 
     block->is_free = 1;
 
-    // Попробуем объединить с соседними свободными блоками
+    /* попробуем объединить с соседними свободными блоками*/
     mem_block_t* current = free_blocks;
     while (current) {
         if (current->is_free && current->next && current->next->is_free) {
-            // Объединяем текущий блок со следующим
+            // соединим текущий блок со следующим
             current->size += sizeof(mem_block_t) + current->next->size;
             current->next = current->next->next;
+            free_mem_addr -= current->size;
         }
         current = current->next;
     }
@@ -112,8 +127,6 @@ meminfo_t get_meminfo() {
     u32 total_free = 0;
     u32 block_count = 0;
 
-    kprint("Memory dump:\n");
-
     while (current) {
         block_count++;
 
@@ -137,46 +150,19 @@ meminfo_t get_meminfo() {
     return meminfo;
 }
 
-void kmemdump() { // дамп памяти
-    mem_block_t* current = free_blocks;
-    u32 total_used = 0;
-    u32 total_free = 0;
-    u32 block_count = 0;
+void kmemdump() {
+    meminfo_t info = get_meminfo();
+    mem_block_t* current = info.free_blocks;
+    u32 counter = 0;
 
-    kprint("Memory dump:\n");
+    kprintf("Heap: %x - %x (%d bytes)\n", info.heap_start, info.heap_start + info.heap_size, info.heap_size);
+    kprintf("Block size: %d bytes\n", info.block_size);
+    kprintf("Total: USED=%d bytes, FREE=%d bytes, in %d blocks\n\n", info.total_used, info.total_free, info.block_count);
 
     while (current) {
-        kprint("Block ");
-        char buf[32];
-        int_to_ascii(block_count++, buf);
-        kprint(buf);
-        kprint(": Addr=");
-        hex_to_ascii((u32)current, buf);
-        kprint(buf);
-        kprint(", Size=");
-        int_to_ascii(current->size, buf);
-        kprint(buf);
-        kprint(", ");
-        kprint(current->is_free ? "FREE" : "USED");
-        kprint("\n");
-
-        if (current->is_free) {
-            total_free += current->size;
-        } else {
-            total_used += current->size;
-        }
-
+        kprintf("Block %d: %x, Size=%d, %s\n", counter++, (u32)current, current->size, current->is_free ? "FREE" : "USED");
         current = current->next;
     }
-
-    kprint("Total: USED=");
-    char buf2[32];
-    int_to_ascii(total_used, buf2);
-    kprint(buf2);
-    kprint(", FREE=");
-    int_to_ascii(total_free, buf2);
-    kprint(buf2);
-    kprint("\n");
 }
 
 // LEGACY Arena

src/kernel/libc/mem.h

@@ -28,9 +28,9 @@ typedef struct meminfo {
     u32 total_used;
     u32 total_free;
     u32 block_count;
-
 } meminfo_t;
 
+void *get_physaddr(void *virtualaddr);
 meminfo_t get_meminfo();
 void memory_copy(u8 *source, u8 *dest, int nbytes);
 void memory_set(u8 *dest, u8 val, u32 len);

src/kernel/libc/string.c

@@ -59,6 +59,18 @@ void strcpy(char *dest, char *src) {
     *dest = '\0';
 }
 
+int hex_strtoint(char *str) {
+    int result = 0;
+    while (*str) {
+        result *= 16;
+        if (*str >= '0' && *str <= '9') result += *str - '0';
+        else if (*str >= 'a' && *str <= 'f') result += *str - 'a' + 10;
+        else if (*str >= 'A' && *str <= 'F') result += *str - 'A' + 10;
+        str++;
+    }
+    return result;
+}
+
 /* K&R */
 void reverse(char s[]) {
     int c, i, j;

src/kernel/libc/string.h

@@ -9,6 +9,7 @@ int strlen(char s[]);
 void backspace(char s[]);
 void append(char s[], char n);
 int strcmp(char s1[], char s2[]);
+int hex_strtoint(char *str);
 void strcpy(char *dest, char *src);
 unsigned int is_delim(char c, char *delim);
 char *strtok(char *src_str, char *delim);