resize.c pseudocode

/**
* Pseudo code for resize.c
* Program to enlarge a BMP image by factor of n (number passed in as argument to program when running it).
* begin main
*     if argc is not equal to 4
*         print out message for correct usage
*         return 1 for error
*     end if
*     store filename of input file (argv[2]) in variable of type char *
*     store filename of output file (argv[3]) in another variable of type char *
*     create a variable of type int and store in it the return value of atoi() with
*     argv[1] passed into it (this is the number, n, which will be used as the factor to resize the image by).
*     if the value of n is not between 1 and 100 (inclusive)
*         print out an error message
*         return 2 for error
*     end if
*     declare file pointer variable and store the name of the input file in it, and try to open file for reading
*     if the file couldn't be opened (and file pointer is NULL)
*         print out error message
*         return 3 for error
*     end if
*     try to open the output file for writing, declared as a file pointer variable
*     if the file couldn't be opened (and file pointer is NULL)
*         print out error message
*         return 4 for error
*     read input file's BITMAPFILEHEADER, after declaring a variable of type BITMAPFILEHEADER
*     read input file's BITMAPINFOHEADER, after declaring a variable of type BITMAPINFOHEADER
*     if BMP file is not a 24-bit uncompressed BMP 4.0 (likely)
*         close input file
*         close outtput file
*         print error message
*         return 4 for error
*     end if
*     remember the input file's padding, storing it an integer variable named padding (be sure to calculate it correctly)
*     remember original image's dimensions as integer variables img_width and img_height
*     calculate resized image's dimensions by multiplying original by factor of n
*     calculate resized image's padding
*     update the header info for the resized image, calculating the new bfSize and biSizeImage
*     write outfiles BITMAPFILEHEADER and BITMAPINFOHEADER using fwrite
*     iterate over input file's scanlines in a for loop, going from 0 until the height of the original image - 1
*         iterate over pixels in scanline in an inner for loop, going from 0 to the width of the orignal image - 1 to resize horizontally
*             declare RGBTRIPLE variabl for temporary storage
*             read into storage from input file
*             for 0 to n - 1 times
*                 write into output file the RGBTRIPLE data, by as many bytes as RGBTRIPLE, one byte on each iteration
*             end for
*         for 0 to output file scanline padding
*             put in a 0 for the padding
*         end for
*         skip over input file padding
*         for 0 to original image width, iterate over the image's width to resize vertically
*             create another temporary storage place RGBTRIPLEs
*             read triples data from input file and store it
*             for 0 to as many times as the original image's height
*                 write into output file the RGBTRIPLE data, by as many bytes as RGBTRIPLE, one byte on each iteration
*             end for
*         end for
*         rewind cursor by size of the input file padding
*        end for
*     end for
*     close input file
*     close output file
*     return 0 for success
* end main
*/