feat(file_parser.s): Function for parsing file into array format

1 files changed, 58 insertions, 0 deletions

diff --git a/src/file_parser.s b/src/file_parser.s
new file mode 100644
index 0000000..059dabf
--- /dev/null
+++ b/src/file_parser.s
@@ -0,0 +1,58 @@
+# --------------------------------------------
+# FUNCTION: parse_file
+# PURPOSE : Parses the file into the array format.
+# INPUTS  : rdi = File descriptor
+# OUTPUTS : rax = address of array
+# CLOBBERS: none
+# NOTES   : Preserves all registers.
+# --------------------------------------------
+.section .text
+.globl parse_file
+.type parse_file, @function
+parse_file:
+    # Save registers
+    push %rbx
+    push %rbp
+    push %r12
+    push %r13
+    push %r14
+    push %r15
+
+    movq %rdi, %r15     # Save file descriptor in r15
+    movq %r15, %rdi     # Select file descriptor
+    call getFileSize    # Get the file size
+    movq %rax, %r14     # Save file size in r14
+
+    movq %r14, %rdi     # Select file size
+    call allocate       # Allocate memory for file contents
+    movq %rax, %r13     # Save file buffer in r13
+
+    movq %r15, %rdi     # Select the file discriptor
+    movq %r13, %rsi     # Select the buffer to store input
+    movq %r14, %rdx     # Size to read from file
+    movq $0, %rax       # Select read syscall
+    syscall             # Read from the file
+
+    movq %r13, %rdi     # Select buffer for file contents
+    movq %r14, %rsi     # Select file size
+    call getLineCount   # Count lines
+    movq %rax, %r12     # Save line count in r12
+
+    movq %r12, %rdi     # Select number of coordinates
+    call make_coordinate_buffer # Create buffer
+    movq %rax, %r13     # Override file buffer with coordinate buffer
+
+    movq %r13, %rdi     # Select coordinate buffer
+    movq %r12, %rsi     # Select number of coordinates
+    call build_pointer_buffer   # Create final array of pointers
+    movq %rax, %r13     # Override r13 with pointer to array
+
+    # Restore registers
+    pop %r15
+    pop %r14
+    pop %r13
+    pop %r12
+    pop %rbp
+    pop %rbx
+
+    ret