common(stdio): implement %p and %#x printf formats

.clang-tidy

@@ -19,9 +19,8 @@ Checks: >
     -readability-braces-around-statements,
     -readability-identifier-length,
     -readability-magic-numbers,
-    -readability-inconsistent-declaration-parameter-name
+    -readability-inconsistent-declaration-parameter-name,
+    -readability-function-cognitive-complexity,
 CheckOptions:
     - key: bugprone-narrowing-conversions.WarnOnIntegerNarrowingConversion
       value: false
-    - key: readability-function-cognitive-complexity.Threshold
-      value: 100

common/stdio.c

@@ -59,34 +59,44 @@ int vsnprintf(char* buffer, size_t size, const char* format, va_list args) {
         return 0;
 
     size_t idx = 0;
+
+#define PUT(c)                                                                 \
+    do {                                                                       \
+        buffer[idx++] = (c);                                                   \
+        if (idx >= size)                                                       \
+            goto too_long;                                                     \
+    } while (0)
+
     char ch;
     while ((ch = *format++) != 0) {
         if (ch != '%') {
-            buffer[idx++] = ch;
-            if (idx >= size)
-                goto too_long;
+            PUT(ch);
             continue;
         }
 
         ch = *format++;
         if (ch == '%') {
-            buffer[idx++] = '%';
-            if (idx >= size)
-                goto too_long;
+            PUT('%');
             continue;
         }
 
+        bool alternative_form = false;
         bool left_justify = false;
         bool pad0 = false;
         size_t pad_len = 0;
-
-        if (ch == '-') {
-            left_justify = true;
-            ch = *format++;
-        }
-        if (ch == '0') {
-            pad0 = true;
-            ch = *format++;
+        for (;;) {
+            if (!alternative_form && ch == '#') {
+                alternative_form = true;
+                ch = *format++;
+            } else if (!left_justify && ch == '-') {
+                left_justify = true;
+                ch = *format++;
+            } else if (!pad0 && ch == '0') {
+                pad0 = true;
+                ch = *format++;
+            } else {
+                break;
+            }
         }
         while ('0' <= ch && ch <= '9') {
             pad_len = pad_len * 10 + ch - '0';
@@ -95,36 +105,36 @@ int vsnprintf(char* buffer, size_t size, const char* format, va_list args) {
 
         switch (ch) {
         case 'c':
-            buffer[idx++] = (char)va_arg(args, int);
-            if (idx >= size)
-                goto too_long;
+            PUT((char)va_arg(args, int));
             break;
+        case 'p':
+        case 'x':
+            if (alternative_form || ch == 'p') {
+                PUT('0');
+                if (pad_len > 0)
+                    --pad_len;
+                PUT('x');
+                if (pad_len > 0)
+                    --pad_len;
+            }
+            // falls through
         case 'd':
         case 'i':
-        case 'u':
-        case 'x': {
+        case 'u': {
             char num_buf[20];
-            itoa(va_arg(args, int), num_buf, ch == 'x' ? 16 : 10);
+            int radix = (ch == 'x' || ch == 'p') ? 16 : 10;
+            itoa(va_arg(args, int), num_buf, radix);
 
             size_t len = strlen(num_buf);
             if (!left_justify && pad_len > len) {
-                for (size_t i = 0; i < pad_len - len; ++i) {
-                    buffer[idx++] = pad0 ? '0' : ' ';
-                    if (idx >= size)
-                        goto too_long;
-                }
-            }
-            for (size_t i = 0; i < len; ++i) {
-                buffer[idx++] = num_buf[i];
-                if (idx >= size)
-                    goto too_long;
+                for (size_t i = 0; i < pad_len - len; ++i)
+                    PUT(pad0 ? '0' : ' ');
             }
+            for (size_t i = 0; i < len; ++i)
+                PUT(num_buf[i]);
             if (left_justify && pad_len > len) {
-                for (size_t i = 0; i < pad_len - len; ++i) {
-                    buffer[idx++] = ' ';
-                    if (idx >= size)
-                        goto too_long;
-                }
+                for (size_t i = 0; i < pad_len - len; ++i)
+                    PUT(' ');
             }
 
             break;
@@ -133,17 +143,12 @@ int vsnprintf(char* buffer, size_t size, const char* format, va_list args) {
             const char* str = va_arg(args, const char*);
             if (!str)
                 str = "(null)";
-            while (*str) {
-                buffer[idx++] = *str++;
-                if (idx >= size)
-                    goto too_long;
-            }
+            while (*str)
+                PUT(*str++);
             break;
         }
         default:
-            buffer[idx++] = '?';
-            if (idx >= size)
-                goto too_long;
+            PUT('?');
             break;
         }
     }

kernel/drivers/graphics/bochs.c

@@ -90,7 +90,7 @@ struct fb* bochs_fb_init(void) {
     if (!phys_addr)
         return NULL;
 
-    kprintf("bochs_fb: found framebuffer at P0x%x\n", phys_addr);
+    kprintf("bochs_fb: found framebuffer at P%#x\n", phys_addr);
     configure(640, 480, 32);
 
     static struct fb fb = {.get_info = bochs_fb_get_info,

kernel/drivers/graphics/multiboot.c

@@ -37,7 +37,7 @@ struct fb* multiboot_fb_init(const multiboot_info_t* mb_info) {
     info.height = mb_info->framebuffer_height;
     info.pitch = mb_info->framebuffer_pitch;
     info.bpp = mb_info->framebuffer_bpp;
-    kprintf("multiboot_fb: found framebuffer at P0x%x\n", phys_addr);
+    kprintf("multiboot_fb: found framebuffer at P%#x\n", phys_addr);
 
     static struct fb fb = {.get_info = multiboot_fb_get_info,
                            .set_info = multiboot_fb_set_info,

kernel/fs/vfs.c

@@ -22,7 +22,7 @@ void vfs_init(void) {
 }
 
 void vfs_populate_root_fs(const multiboot_module_t* initrd_mod) {
-    kprintf("vfs: populating root fs with initrd at P0x%x - P0x%x\n",
+    kprintf("vfs: populating root fs with initrd at P%#x - P%#x\n",
             initrd_mod->mod_start, initrd_mod->mod_end);
     initrd_populate_root_fs(initrd_mod->mod_start,
                             initrd_mod->mod_end - initrd_mod->mod_start);

kernel/idt.c

@@ -144,10 +144,10 @@ static void handle_exception14(registers* regs) {
     uint32_t write = regs->err_code & 0x2;
     uint32_t user = regs->err_code & 0x4;
 
-    kprintf("Page fault (%s%s%s) at 0x%x\n",
+    kprintf("Page fault (%s%s%s) at %p\n",
             present ? "page-protection " : "non-present ",
             write ? "write " : "read ", user ? "user-mode" : "kernel-mode",
-            read_cr2());
+            (void*)read_cr2());
     crash(regs, SIGSEGV);
 }
 

kernel/main.c

@@ -34,8 +34,8 @@ noreturn void start(uint32_t mb_magic, uintptr_t mb_info_phys_addr) {
     sti();
 
     kprintf("version: %s\n"
-            "kernel end: V0x%x\n",
-            utsname()->version, (uintptr_t)kernel_end);
+            "kernel end: V%p\n",
+            utsname()->version, kernel_end);
     ASSERT(mb_magic == MULTIBOOT_BOOTLOADER_MAGIC);
 
     const multiboot_info_t* mb_info =

kernel/memory/page.c

@@ -144,7 +144,7 @@ void page_init(const multiboot_info_t* mb_info) {
     uintptr_t lower_bound;
     uintptr_t upper_bound;
     get_available_physical_addr_bounds(mb_info, &lower_bound, &upper_bound);
-    kprintf("page: available physical memory address space P0x%x - P0x%x\n",
+    kprintf("page: available physical memory address space P%#x - P%#x\n",
             lower_bound, upper_bound);
 
     bitmap_init(mb_info, lower_bound, upper_bound);

kernel/memory/page_table.c

@@ -269,7 +269,7 @@ void page_directory_switch(struct page_directory* to) {
 }
 
 void page_table_init(void) {
-    kprintf("page_table: kernel page directory is at P0x%x\n",
+    kprintf("page_table: kernel page directory is at P%#x\n",
             (uintptr_t)kernel_page_directory_start);
 
     // Populate page directory entries for kernel space so that all processes