Make code ANSI C compatible

5 files changed, 31 insertions, 36 deletions

diff --git a/src/boot.h b/src/boot.h
index 8d62bdc..646fb4c 100644
--- a/src/boot.h
+++ b/src/boot.h
@@ -1,24 +1,21 @@
-#pragma once
+/* *** glitch kernel ***
+ * spdx-license-identifier: ISC
+ * description: kernel boot information
+ * */
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+#pragma once
 
 typedef struct {
-  // kernel command line
+  /* kernel command line */
   char cmdline[64];
 
-  // memory map
+  /* memory map */
   unsigned bitmap[1024 * 32];
 
-  // module
+  /* module */
   unsigned module_start;
   unsigned module_end;
   char module_cmdline[64];
 } boot_info_t;
 
-_Static_assert((1024 * 32 * sizeof(unsigned) * 8) == (1024 * 1024), "bitmap size check");
-
-#ifdef __cplusplus
-}
-#endif
+/* TODO _Static_assert((1024 * 32 * sizeof(unsigned) * 8) == (1024 * 1024), "bitmap size check"); */
diff --git a/src/kernel.c b/src/kernel.c
index 3ee231e..8d7560b 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -1,8 +1,7 @@
-//=====================================================================
-// glitch kernel
-// spdx-license-identifier: ISC
-// description: kernel entry point
-//=====================================================================
+/* *** glitch kernel ***
+ * spdx-license-identifier: ISC
+ * description: kernel entry point
+ * */
 
 #include "conf.h"
 #include "mem.h"
diff --git a/src/mem/vmm.c b/src/mem/vmm.c
index 77b06a8..f62eadf 100644
--- a/src/mem/vmm.c
+++ b/src/mem/vmm.c
@@ -18,8 +18,8 @@ vmm_map(unsigned int paddr, unsigned int vaddr)
 {
   if (paddr & 0xfff || vaddr & 0xfff) return 0;
 
-  const unsigned table_idx = vaddr >> 22;             // high 10 bits
-  const unsigned entry_idx = (vaddr >> 12) & 0x3ff;   // low 10 bits
+  const unsigned table_idx = vaddr >> 22;           /* high 10 bits */
+  const unsigned entry_idx = (vaddr >> 12) & 0x3ff; /* low 10 bits */
 
   if (k_pagedir[table_idx].present == 0) return 0;
   struct TableEntry *table = (struct TableEntry *)to_vaddr(k_pagedir[table_idx].address << 12);
@@ -34,12 +34,8 @@ vmm_map(unsigned int paddr, unsigned int vaddr)
 void
 alloc4M()
 {
-  // enable pse in cr4
-  asm volatile(R"(
-  movl %cr4, %eax
-  orl $0x10, %eax
-  movl %eax, %cr4
-)");
+  /* enable pse in cr4 */
+  __asm__("movl %cr4, %eax; orl $0x10, %eax; movl %eax, %cr4");
 
   struct DirectoryEntry4MB *directory = (struct DirectoryEntry4MB *)&k_pagedir[0x301];
   directory->address_low = 0x1;
diff --git a/src/mmap.c b/src/mmap.c
index 3fe35b5..c28ce79 100644
--- a/src/mmap.c
+++ b/src/mmap.c
@@ -6,15 +6,17 @@
 __attribute__((section(".multiboot.text"))) unsigned
 multiboot2_mmap(const struct multiboot_mmap_entry entries[], unsigned entry_count, unsigned bitmap[1024 * 32])
 {
-  // clear out the bitmap
-  for (unsigned i = 0; i < 1024 * 32; ++i) bitmap[i] = 0;
+  unsigned i, l;
+
+  /* clear out the bitmap */
+  for (i = 0; i < 1024 * 32; ++i) bitmap[i] = 0;
   unsigned avail_frames = 0;
 
-  // loop through all the mmap_entry structures where type is MULTIBOOT_MEMORY_AVAILABLE
-  for (unsigned i = 0; i < entry_count; ++i) {
+  /* loop through all the mmap_entry structures where type is MULTIBOOT_MEMORY_AVAILABLE */
+  for (i = 0; i < entry_count; ++i) {
     if (entries[i].type != MULTIBOOT_MEMORY_AVAILABLE) continue;
 
-    // number of frames in this entry
+    /* number of frames in this entry */
     unsigned n_frames = entries[i].len / 4096;
     avail_frames += n_frames;
 
@@ -23,8 +25,8 @@ multiboot2_mmap(const struct multiboot_mmap_entry entries[], unsigned entry_coun
            n_frames / 32, n_frames % 32);
 #endif
 
-    // the bitmap is an array of blocks, each holding 32 (2^5) values
-    unsigned table_idx = (entries[i].addr >> 17); // get the upper 15 bits
+    /* the bitmap is an array of blocks, each holding 32 (2^5) values */
+    unsigned table_idx = (entries[i].addr >> 17); /* get the upper 15 bits */
 
     while (n_frames != 0) {
       if (n_frames >= 32) {
@@ -34,7 +36,7 @@ multiboot2_mmap(const struct multiboot_mmap_entry entries[], unsigned entry_coun
       }
       else {
         unsigned block = bitmap[table_idx];
-        for (unsigned l = 0; l < n_frames; ++l) block |= (1 << l);
+        for (l = 0; l < n_frames; ++l) block |= (1 << l);
         bitmap[table_idx] = block;
         n_frames = 0;
       }
diff --git a/src/multiboot2.c b/src/multiboot2.c
index ea06e96..bd6250f 100644
--- a/src/multiboot2.c
+++ b/src/multiboot2.c
@@ -7,7 +7,8 @@ boot_info_t info __attribute__((section(".init")));
 __attribute__((section(".multiboot.text"))) void
 multiboot_strncpy(char *dest, const char *src, unsigned n)
 {
-  for (unsigned i = 0; i < n && src[i] != '\0'; ++i) dest[i] = src[i];
+  unsigned i;
+  for (i = 0; i < n && src[i] != '\0'; ++i) dest[i] = src[i];
 }
 
 __attribute__((section(".multiboot.text"))) void
@@ -44,6 +45,6 @@ __multiboot2(multiboot_uint32_t addr)
       break;
     default:
       break;
-    } // switch
-  }   // for
+    }
+  }
 }