trying to get VGA fb mode to work..

rocklibc/compile_commands.json

@@ -16,6 +16,40 @@
     "file": "/home/slinky/source/RockOS/rocklibc/src/string.c",
     "output": "/home/slinky/source/RockOS/rocklibc/src/string.o"
   },
+  {
+    "arguments": [
+      "/home/slinky/opt/cross/bin/i686-elf-gcc",
+      "-ffreestanding",
+      "-O2",
+      "-Wall",
+      "-Wextra",
+      "-Iinclude",
+      "-c",
+      "-o",
+      "src/malloc.o",
+      "src/malloc.c"
+    ],
+    "directory": "/home/slinky/source/RockOS/rocklibc",
+    "file": "/home/slinky/source/RockOS/rocklibc/src/malloc.c",
+    "output": "/home/slinky/source/RockOS/rocklibc/src/malloc.o"
+  },
+  {
+    "arguments": [
+      "/home/slinky/opt/cross/bin/i686-elf-gcc",
+      "-ffreestanding",
+      "-O2",
+      "-Wall",
+      "-Wextra",
+      "-Iinclude",
+      "-c",
+      "-o",
+      "src/strcat.o",
+      "src/strcat.c"
+    ],
+    "directory": "/home/slinky/source/RockOS/rocklibc",
+    "file": "/home/slinky/source/RockOS/rocklibc/src/strcat.c",
+    "output": "/home/slinky/source/RockOS/rocklibc/src/strcat.o"
+  },
   {
     "arguments": [
       "/home/slinky/opt/cross/bin/i686-elf-gcc",
@@ -33,6 +67,23 @@
     "file": "/home/slinky/source/RockOS/rocklibc/src/syscall.c",
     "output": "/home/slinky/source/RockOS/rocklibc/src/syscall.o"
   },
+  {
+    "arguments": [
+      "/home/slinky/opt/cross/bin/i686-elf-gcc",
+      "-ffreestanding",
+      "-O2",
+      "-Wall",
+      "-Wextra",
+      "-Iinclude",
+      "-c",
+      "-o",
+      "src/strtok.o",
+      "src/strtok.c"
+    ],
+    "directory": "/home/slinky/source/RockOS/rocklibc",
+    "file": "/home/slinky/source/RockOS/rocklibc/src/strtok.c",
+    "output": "/home/slinky/source/RockOS/rocklibc/src/strtok.o"
+  },
   {
     "arguments": [
       "/home/slinky/opt/cross/bin/i686-elf-gcc",

rocklibc/include/stdlib.h

@@ -0,0 +1,8 @@
+#ifndef RLIBC_STDLIB_H
+#define RLIBC_STDLIB_H
+
+#include <stddef.h>
+
+void* malloc(size_t size);
+
+#endif

rocklibc/include/string.h

@@ -10,5 +10,6 @@ void *memset(void *s, int c, size_t n);
 size_t strlen(const char *s);
 int strcmp(const char *s1, const char *s2);
 char *strcpy(char *dest, const char *src);
+char* strcat(char *dest, const char* src);
 
 #endif

rocklibc/include/syscall.h

@@ -9,6 +9,8 @@
 #define SYS_WRITE   4
 #define SYS_OPEN    5
 #define SYS_CLOSE   6
+#define SYS_BRK     12
+#define SYS_SBRK    13
 #define SYS_PTY     20
 #define SYS_FORK    21
 #define SYS_EXEC    22
@@ -25,7 +27,7 @@ int lseek(int fd, size_t offset, int whence);
 
 void exit(int status) __attribute__((noreturn));
 
-void *sbrk(intptr_t increment);
+void* sbrk(int32_t increment);
 int brk(void *addr);
 
 int pty(int* slave);

rocklibc/src/malloc.c

@@ -0,0 +1,74 @@
+#include <stdlib.h>
+#include <syscall.h>
+
+#define ALIGN(size) (((size) + 3) & ~3)
+#define HEADER_SIZE sizeof(struct Header)
+
+struct Header {
+    size_t size;
+    int is_free;
+    struct Header* next;
+};
+
+static struct Header* free_list_head = NULL;
+
+static struct Header* find_free_block(struct Header** last, size_t size) {
+    struct Header* current = free_list_head;
+    while (current && !(current->is_free && current->size >= size)) {
+        *last = current;
+        current = current->next;
+    }
+    return current;
+}
+
+static struct Header* request_space(struct Header* last, size_t size) {
+    struct Header* block = sbrk(0);
+    void* request = sbrk(size + HEADER_SIZE);
+    
+    if (request == (void*)-1) {
+        return NULL;
+    }
+    
+    if (last) {
+        last->next = block;
+    }
+    
+    block->size = size;
+    block->next = NULL;
+    block->is_free = 0;
+    return block;
+}
+
+void* malloc(size_t size) {
+    if (size <= 0) {
+        return NULL;
+    }
+    
+    size = ALIGN(size);
+    
+    if (free_list_head == NULL) {
+        struct Header* block = request_space(NULL, size);
+        if (!block) return NULL;
+        free_list_head = block;
+        return (void*)(block + 1);
+    }
+    
+    struct Header* last = free_list_head;
+    struct Header* block = find_free_block(&last, size);
+    
+    if (block) {
+        block->is_free = 0;
+    } else {
+        block = request_space(last, size);
+        if (!block) return NULL;
+    }
+    
+    return (void*)(block + 1);
+}
+
+void free(void* ptr) {
+    if (!ptr) return;
+    
+    struct Header* block = (struct Header*)ptr - 1;
+    block->is_free = 1;
+}

rocklibc/src/strcat.c

@@ -0,0 +1,8 @@
+#include <string.h>
+#include <stdint.h>
+
+char* strcat(char* dest, const char* src) {
+    char* start = dest + strlen(dest);
+    strcpy(start, src);
+    return dest;
+}

rocklibc/src/strtok.c

@@ -0,0 +1,63 @@
+#include <string.h>
+
+static size_t kernel_strspn(const char *s, const char *accept) {
+    const char *p;
+    const char *a;
+    size_t count = 0;
+
+    for (p = s; *p != '\0'; ++p) {
+        for (a = accept; *a != '\0'; ++a) {
+            if (*p == *a)
+                break;
+        }
+        if (*a == '\0')
+            return count;
+        ++count;
+    }
+    return count;
+}
+
+static char *kernel_strpbrk(const char *s, const char *accept) {
+    while (*s != '\0') {
+        const char *a = accept;
+        while (*a != '\0') {
+            if (*s == *a) {
+                return (char *)s;
+            }
+            a++;
+        }
+        s++;
+    }
+    return NULL;
+}
+
+char *strtok_r(char *str, const char *delim, char **saveptr) {
+    char *token;
+
+    if (str == NULL) {
+        str = *saveptr;
+    }
+
+    if (str == NULL || *str == '\0') {
+        *saveptr = NULL;
+        return NULL;
+    }
+
+    str += kernel_strspn(str, delim);
+    if (*str == '\0') {
+        *saveptr = NULL;
+        return NULL;
+    }
+
+    token = str;
+    str = kernel_strpbrk(token, delim);
+    
+    if (str == NULL) {
+        *saveptr = NULL;
+    } else {
+        *str = '\0';
+        *saveptr = str + 1;
+    }
+
+    return token;
+}

rocklibc/src/syscall.c

@@ -65,4 +65,12 @@ int dup2(int src, int dst) {
 
 int waitpid(int pid, int* status) {
     return syscall3(SYS_WAIT, pid, (uint32_t)status, 0);
+}
+
+void* sbrk(int32_t increment) {
+    return (void*)syscall1(SYS_SBRK, increment);
+}
+
+int brk(void *addr) {
+    return syscall1(SYS_BRK, (uint32_t)addr);
 }