From 06e6e427c76bdb88a7f72dd04411d95a4bda3270 Mon Sep 17 00:00:00 2001
From: Miguel <m.i@gmx.at>
Date: Sun, 16 Sep 2018 23:46:30 +0200
Subject: starting to create sysfs

---
 fs/mount.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)
 create mode 100644 fs/mount.c

(limited to 'fs/mount.c')

diff --git a/fs/mount.c b/fs/mount.c
new file mode 100644
index 0000000..a7cd949
--- /dev/null
+++ b/fs/mount.c
@@ -0,0 +1,96 @@
+#include <stddef.h>
+
+#include "kernel.h"
+#include "mount.h"
+
+#include "log.h"
+
+#include "lib/string/string.h"
+// temporary
+#include "fd.h"
+
+static mount mounts[MAX_MOUNTS];
+static uint32_t mounts_count=0;
+
+char *mount_type_to_str(uint32_t t)
+{
+    switch(t)
+    {
+	case MOUNT_TYPE_EXT2:  return "EXT2";
+	case MOUNT_TYPE_PIPES: return "PIPES";
+	case MOUNT_TYPE_SYS:   return "SYS";
+    }
+    return "UNKNOWN";
+}
+
+void mount_add(mount mnt)
+{
+    if(mounts_count==MAX_MOUNTS)kpanic("maxium number of mounts exceeded. increase MAX_MOUNTS in kernel.h and recomplie kernel.");
+    mounts[mounts_count++]=mnt;
+    klog("mounted %s",mnt.path);
+}
+
+void mount_dump()
+{
+    for(int i=0;i<mounts_count;i++)
+    {
+	mount *m=&mounts[i];
+	klog("%s mounted at: %s ",mount_type_to_str(m->type),m->path);
+    }
+}
+
+static uint32_t check_match(char *p1, char *p2)
+{
+    uint32_t c=0;
+    while(1)
+    {
+	if(*p1==0||*p2==0||*p1!=*p2)return c;
+	c++;
+	p1++;
+	p2++;
+    }
+}
+
+/** 
+ *  Find the mountpoint correspoding with the given path and return in _mnt_ parameter.
+ *  The return value points to the input path with chopped of prefix indicating the mount itself. 
+ *  returns 0 if mount not found.
+ */
+static char* get_mount_for_path(char *path,mount *mnt)
+{
+    if(path[0]!='/')kpanic("this works only for absolute paths!");
+
+    uint32_t best=0;
+    uint32_t best_len=0;
+    
+    for(int i=0;i<mounts_count;i++)
+    {
+	mount *m=&mounts[i];
+	uint32_t len=check_match(path,m->path);
+
+	if(len>best_len&&len==strlen(m->path))
+	{
+	    best=i;
+	    best_len=len;
+	}
+
+    }
+    if(best_len==0)return 0;
+    *mnt=mounts[best];
+    return path+best_len-1;
+}
+
+fd mount_file_open(char *path)
+{
+    mount m;
+    char *p=get_mount_for_path(path,&m);
+    klog("%s in %s",p,m.path);
+    return m.mount_file_open(&m,p);
+}
+
+int mount_read_dir (char *path, fs_dirent *dirs, uint32_t *pos)
+{
+    mount m;
+    char *p=get_mount_for_path(path,&m);
+    return m.mount_read_dir(&m,p,dirs,pos);
+}
-- 
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