[USER] Init libc with arguments and environment

MESS - execve - Clean up and move earlier

kernel/proc/exec_elf.c

@@ -1,14 +1,80 @@
 #include <elf.h>
 #include <stdint.h>
 #include <debug.h>
+#include <mem.h>
+#include <string.h>
+#include <process.h>
 
-thread_t *exec_elf(process_t *p, void *image)
+thread_t *exec_elf(process_t *p, void *image, char *argv[], char *envp[])
 {
+  int argc = 0, envc=0;
+  // Count strings and save their lengths
+  int len = 0;
+  while(argv[argc]){
+    len += strlen(argv[argc]) + 1;
+    argc++;
+  }
+  len += (argc+1)*sizeof(char *);
+  while(envp[envc])
+  {
+    len += strlen(envp[envc]) + 1;
+    envc++;
+  }
+  len += (envc+1)*sizeof(char *);
+  len += sizeof(size_t)*2;
+  len += sizeof(char);
+
+  // Replace process memory space with new image
   void *entry = load_elf(p, image);
-  debug("Address:%x\n", entry);
-  procmm_setup(p);
+  procmm_setup(p, len);
+
+  // We will write to process memory, so let's switch to it
+  vmm_set_P4(p->mmap->P4);
+
+
+  // Memory layout of area before BRK
+  // argv[]
+  // 0
+  // envp[]
+  // 0
+  // auxv[]
+  // arguments
+  // env strings
+  // 0
+  // BRK points here
+  void *pos = (void *)p->mmap->brk->start;
+  char **_argv = pos;
+  pos = incptr(pos, (argc+1)*sizeof(char *));
+  char **_envp = pos;
+  pos = incptr(pos, (envc+1)*sizeof(char *));
+  size_t *_auxv = pos;
+  pos = incptr(pos, sizeof(size_t)*2);
+
+  // Copy arguments
+  for(int i = 0; i < argc; i++)
+  {
+    size_t len = strlen(argv[i]) + 1;
+    _argv[i] = pos;
+    memcpy(_argv[i], argv[i], len);
+    pos = incptr(pos, len);
+  }
+  _argv[argc] = 0;
+  // Copy environment strings
+  for(int i = 0; i < envc; i++)
+  {
+    size_t len = strlen(envp[i]) + 1;
+    _envp[i] = pos;
+    memcpy(_envp[i], envp[i], len);
+    pos = incptr(pos, len);
+  }
+  _envp[envc] = 0;
+  // No auxiliary vectors for now
+  _auxv[0] = 0;
+
   thread_t *th = new_thread((void *)entry, 1);
   process_attach(p, th);
+  th->r.rsi = (uint64_t)_argv;
+  th->r.rdi = argc;
 
   return th;
 }

kernel/proc/procmm.c

@@ -103,13 +103,13 @@ void procmm_unmap(procmm_area_t *a)
   kfree(a);
 }
 
-uintptr_t procmm_setup(process_t *proc)
+int procmm_setup(process_t *proc, size_t brk_size)
 {
   procmm_mmap_t *map = proc->mmap;
   procmm_area_t *last_a = map->areas.prev;
 
   uintptr_t brk_start = (last_a->end + PAGE_SIZE) & ~(PAGE_SIZE-1);
-  map->brk = procmm_map(map, brk_start, brk_start, 0);
+  map->brk = procmm_map(map, brk_start, brk_start + brk_size, 0);
 
   map->stack = procmm_map(map, USERSPACE_TOP, USERSPACE_TOP, 0);