Implement environment variables

kernel/proc/env.c

@@ -0,0 +1,83 @@
+#include <libk/fieldlengthof.h>
+#include <libk/hash.h>
+#include <libk/lengthof.h>
+#include <libk/minmax.h>
+#include <libk/std.h>
+#include <libk/string.h>
+#include <mm/malloc.h>
+#include <proc/env.h>
+#include <proc/proc.h>
+#include <status.h>
+
+void proc_env_cleanup (struct proc* proc) {
+  for (size_t i = 0; i < fieldlengthof (struct proc_env, env_var_buckets); i++) {
+    struct hash_node_link* link = proc->env.env_var_buckets[i];
+
+    if (link == NULL)
+      continue;
+
+    struct proc_env_var* var = hash_entry (link, struct proc_env_var, env_link);
+
+    free (var->buffer);
+    free (var);
+  }
+}
+
+int proc_env_set (struct proc* proc, const char* key, void* buffer, size_t data_size) {
+  uint64_t fp;
+
+  struct proc_env_var* var = malloc (sizeof (*var));
+
+  if (var == NULL)
+    return -ST_OOM_ERROR;
+
+  memset (var, 0, sizeof (*var));
+
+  var->buffer = malloc (data_size);
+
+  if (var->buffer == NULL) {
+    free (var);
+    return -ST_OOM_ERROR;
+  }
+
+  var->data_size = data_size;
+  memcpy (var->key, key, strlen_null (key));
+  memcpy (var->buffer, buffer, data_size);
+
+  uint32_t env_hash = hash_fnv32 (var->key, strlen_null (var->key));
+
+  spin_lock (&proc->lock, &fp);
+
+  hash_insert (&proc->env, &var->env_link, env_hash, lengthof (proc->env.env_var_buckets),
+               env_var_buckets);
+
+  spin_unlock (&proc->lock, fp);
+
+  return ST_OK;
+}
+
+int proc_env_get (struct proc* proc, const char* key, void* buffer, size_t size) {
+  uint64_t fp;
+
+  struct hash_node_link* found_link = NULL;
+  size_t key_len = strlen_null (key);
+  uint32_t hash = hash_fnv32 (key, key_len);
+
+  spin_lock (&proc->lock, &fp);
+
+  hash_find (&proc->env, key, key_len, hash, lengthof (proc->env.env_var_buckets), env_var_buckets,
+             struct proc_env_var, env_link, key, found_link);
+
+  if (found_link == NULL) {
+    spin_unlock (&proc->lock, fp);
+    return -ST_NOT_FOUND;
+  }
+
+  struct proc_env_var* var = hash_entry (found_link, struct proc_env_var, env_link);
+
+  memcpy (buffer, var->buffer, min (size, var->data_size));
+
+  spin_unlock (&proc->lock, fp);
+
+  return ST_OK;
+}

kernel/proc/env.h

@@ -0,0 +1,28 @@
+#ifndef _KERNEL_PROC_ENV_H
+#define _KERNEL_PROC_ENV_H
+
+#include <libk/hash.h>
+#include <libk/std.h>
+
+#define PROC_ENV_VAR_MAX 128
+
+struct proc;
+
+struct proc_env_var {
+  char key[PROC_ENV_VAR_MAX];
+  void* buffer;
+  size_t data_size;
+  struct hash_node_link env_link;
+};
+
+struct proc_env {
+  struct hash_node_link* env_var_buckets[64];
+};
+
+void proc_env_cleanup (struct proc* proc);
+
+int proc_env_set (struct proc* proc, const char* key, void* buffer, size_t data_size);
+
+int proc_env_get (struct proc* proc, const char* key, void* buffer, size_t size);
+
+#endif // _KERNEL_PROC_ENV_H

kernel/proc/proc.h

@@ -7,6 +7,7 @@
 #include <libk/rbtree.h>
 #include <libk/std.h>
 #include <path_defs.h>
+#include <proc/env.h>
 #include <proc/procgroup.h>
 #include <proc/resource.h>
 #include <proc/suspension_q.h>
@@ -48,6 +49,7 @@ struct proc {
   size_t mail_recv_size;
   char cwv[VOLUME_MAX];
   struct proc_suspension_q done_sq;
+  struct proc_env env;
 };
 
 void proc_sched (void);

kernel/proc/src.mk

@@ -3,11 +3,13 @@ c += proc/proc.c \
 		 proc/mutex.c \
 		 proc/procgroup.c \
 		 proc/suspension_q.c \
-		 proc/mail.c
+		 proc/mail.c \
+		 proc/env.c
 
 o += proc/proc.o \
 		 proc/resource.o \
 		 proc/mutex.o \
 		 proc/procgroup.o \
 		 proc/suspension_q.o \
-		 proc/mail.o
+		 proc/mail.o \
+		 proc/env.o