Added stat syscall

This currently only returns the file size, other stats will
follow soon!

4 files changed, 59 insertions, 35 deletions

diff --git a/kernel/features/fs.c b/kernel/features/fs.c
index 41aca78..c17a721 100644
--- a/kernel/features/fs.c
+++ b/kernel/features/fs.c
@@ -96,7 +96,40 @@ void *read_inode(struct inode *in)
 	return buf;
 }
 
-void *read_file(char *path)
+u32 find_inode(const char *name, u32 dir_inode)
+{
+	if (!dir_inode)
+		return (unsigned)-1;
+
+	struct inode *i = get_inode(dir_inode);
+
+	char *buf = malloc(BLOCK_SIZE * i->blocks / 2);
+	memset(buf, 0, BLOCK_SIZE * i->blocks / 2);
+
+	for (u32 q = 0; q < i->blocks / 2; q++) {
+		char *data = buffer_read(i->block[q]);
+		memcpy((u32 *)((u32)buf + q * BLOCK_SIZE), data, BLOCK_SIZE);
+	}
+
+	struct dirent *d = (struct dirent *)buf;
+
+	u32 sum = 0;
+	do {
+		// Calculate the 4byte aligned size of each entry
+		sum += d->total_len;
+		if (strlen(name) == d->name_len &&
+		    strncmp((void *)d->name, name, d->name_len) == 0) {
+			free(buf);
+			return d->inode_num;
+		}
+		d = (struct dirent *)((u32)d + d->total_len);
+
+	} while (sum < (1024 * i->blocks / 2));
+	free(buf);
+	return (unsigned)-1;
+}
+
+struct inode *find_inode_by_path(char *path)
 {
 	if (path[0] != '/')
 		return 0;
@@ -126,38 +159,27 @@ void *read_file(char *path)
 	if ((signed)inode <= 0)
 		return 0;
 
-	return read_inode(get_inode(inode));
+	return get_inode(inode);
 }
 
-u32 find_inode(const char *name, u32 dir_inode)
+void *file_read(char *path)
 {
-	if (!dir_inode)
-		return (unsigned)-1;
-
-	struct inode *i = get_inode(dir_inode);
-
-	char *buf = malloc(BLOCK_SIZE * i->blocks / 2);
-	memset(buf, 0, BLOCK_SIZE * i->blocks / 2);
+	return read_inode(find_inode_by_path(path));
+}
 
-	for (u32 q = 0; q < i->blocks / 2; q++) {
-		char *data = buffer_read(i->block[q]);
-		memcpy((u32 *)((u32)buf + q * BLOCK_SIZE), data, BLOCK_SIZE);
-	}
+u32 file_stat(char *path)
+{
+	struct inode *in = find_inode_by_path(path);
+	assert(in);
+	if (!in)
+		return 0;
 
-	struct dirent *d = (struct dirent *)buf;
+	u32 num_blocks = in->blocks / (BLOCK_SIZE / SECTOR_SIZE);
 
-	u32 sum = 0;
-	do {
-		// Calculate the 4byte aligned size of each entry
-		sum += d->total_len;
-		if (strlen(name) == d->name_len &&
-		    strncmp((void *)d->name, name, d->name_len) == 0) {
-			free(buf);
-			return d->inode_num;
-		}
-		d = (struct dirent *)((u32)d + d->total_len);
+	assert(num_blocks != 0);
+	if (!num_blocks)
+		return 0;
 
-	} while (sum < (1024 * i->blocks / 2));
-	free(buf);
-	return (unsigned)-1;
+	u32 sz = BLOCK_SIZE * num_blocks;
+	return sz;
 }
diff --git a/kernel/features/load.c b/kernel/features/load.c
index 2cbe2e7..d2f1961 100644
--- a/kernel/features/load.c
+++ b/kernel/features/load.c
@@ -11,7 +11,7 @@
 
 int bin_load(char *path, struct proc *proc)
 {
-	char *data = read_file(path);
+	char *data = file_read(path);
 
 	u32 stack = (u32)malloc(0x2000) + 0x1000;
 
@@ -33,7 +33,7 @@ int elf_verify(struct elf_header *h)
 // TODO: Fix elf loading
 void elf_load(char *path, struct proc *proc)
 {
-	char *data = read_file(path);
+	char *data = file_read(path);
 	struct elf_header *h = (struct elf_header *)data;
 
 	if (!elf_verify(h)) {
diff --git a/kernel/features/syscall.c b/kernel/features/syscall.c
index ac89d04..3d70dbb 100644
--- a/kernel/features/syscall.c
+++ b/kernel/features/syscall.c
@@ -33,8 +33,12 @@ void syscall_handler(struct regs *r)
 		free((void *)r->ebx);
 		break;
 	}
+	case SYS_STAT: {
+		r->eax = (u32)file_stat((char *)r->ebx);
+		break;
+	}
 	case SYS_READ: {
-		r->eax = (u32)read_file((char *)r->ebx);
+		r->eax = (u32)file_read((char *)r->ebx);
 		break;
 	}
 	case SYS_WRITE: {
diff --git a/kernel/inc/fs.h b/kernel/inc/fs.h
index 93d2013..156bb8c 100644
--- a/kernel/inc/fs.h
+++ b/kernel/inc/fs.h
@@ -93,9 +93,7 @@ struct file {
 	u32 curr_block_pos;
 };
 
-u32 find_inode(const char *name, u32 dir_inode);
-struct inode *get_inode(u32 i);
-void *read_inode(struct inode *in);
-void *read_file(char *path);
+void *file_read(char *path);
+u32 file_stat(char *path);
 
 #endif