lab8

lab08/Makefile

+#Yegeon Seo
+
+cc = gcc
+EXE = foo
+JAVAC = javac
+JRE = java
+PAGER = less
+TEST_OUT = test.out
+EXP_OUT = expected.out
+
+.PHONY : clean run-py run-c read run-java save-java test-java
+
+foo.o : foo.c foo.h
+			$(cc) -c foo.c
+
+main.o : main.c. foo.h
+			$(cc) -c main.c
+
+$(EXE) : main.o foo.o
+			$(cc) -o$(EXE) main.o foo.o
+
+run-c : $(EXE)
+			./$(EXE)
+
+run-py : foo.py
+			./foo.py
+
+read : README
+			$(PAGER) README
+
+foo.class : foo.java
+				$(JAVAC) foo.java
+
+run-java : foo.class
+			$(JRE) foo
+
+save-java : 
+			$(JRE) foo > $(TEST_OUT)
+	
+test-java : $(TEST_OUT) $(EXP_OUT)
+		-@if diff $(TEST_OUT) $(EXP_OUT) &> /dev/null ; then \
+ 			echo "Passed!" ;\
+		else \
+  			echo "Not the same!" ;\
+		fi
+
+clean : 
+		rm foo.o main.o $(EXE) foo.class test.out
+
+

lab08/csv.c

+/*
+ * csv.c - Implementation for a csv library
+ *
+ * Modified from code in Kernighan & Pike, _The Practice of Programming_
+ *   Copyright (C) 1999 Lucent Technologies 
+ *   Excerpted from 'The Practice of Programming' 
+ *   by Brian W. Kernighan and Rob Pike 
+ *
+ * Kurt Schmidt
+ * 3/2018
+ *
+ * gcc 5.4.0 20160609 on
+ * Linux 4.13.0-32-generic
+ *
+ * EDITOR:  tabstop=2 cols=120
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+#include "csv.h"
+
+
+static char fieldsep[] = "," ; /* field separator chars */
+
+	/***** Prototypes for local helper functions ******/
+static char *advquoted( char* ) ;
+static int split( csv_t* ) ;
+static char *line    = NULL ;  /* input chars */
+static char *sline   = NULL ;  /* line copy used by split */
+static int  maxline  = 0 ;     /* size of line[] and sline[] */
+static char **field  = NULL ;  /* field pointers */
+static int  maxfield = 0 ;     /* size of field[] */
+static int  nfield   = 0 ;     /* number of fields in field[] */
+
+static char fieldsep[] = "," ; /* field separator chars */
+
+static char* advquoted( char* ) ;
+static int split( void ) ;
+
+	/* endofline: check for and consume \r, \n, \r\n, or EOF */
+static int endofline( FILE *fin, int c )
+{
+	int eol ;
+
+	eol = ( c=='\r' || c=='\n' ) ;
+	if( c=='\r' ) {
+		c = getc( fin ) ;
+		if( c!='\n' && c != EOF )
+			ungetc( c, fin ) ;	/* read too far; put c back */
+	}
+	return eol ;
+}
+
+	/* reset: set variables back to starting values */
+static void reset( void )
+{
+	free( line );	 /* free(NULL) permitted by ANSI C */
+	free( sline ) ;
+	free( field ) ;
+	line = NULL ;
+	sline = NULL ;
+	field = NULL ;
+	maxline = maxfield = nfield = 0 ;
+}
+
+	/* csvgetline:  get one line, grow as needed */
+	/* sample input: "LU",86.25,"11/4/1998","2:19PM",+4.0625 */
+char* csvgetline( FILE *fin )
+{	
+	int i, c ;
+	char *newl, *news ;
+
+	if( line==NULL ) {			/* allocate on first call */
+		maxline = maxfield = 1 ;
+		line = (char*) malloc( maxline ) ;
+		sline = (char*) malloc( maxline ) ;
+		field = (char**) malloc( maxfield*sizeof( field[0] )) ;
+		if( line==NULL || sline==NULL || field==NULL) {
+			reset() ;
+			return NULL ;		/* out of memory */
+		}
+	}
+
+	for( i=0; (c=getc( fin ))!=EOF && ! endofline(fin,c); i++ ) {
+		if( i>=maxline-1 ) {	  /* grow line */
+			maxline *= 2;		    /* double current size */
+			newl = (char*) realloc( line, maxline ) ;
+			if( newl==NULL ) {
+				reset() ;
+				return NULL ;
+			}
+			line = newl ;
+			news = (char*) realloc( sline, maxline ) ;
+			if( news==NULL ) {
+				reset() ;
+				return NULL ;
+			}
+			sline = news ;
+		}
+		line[i] = c ;
+	}  /* for i */
+
+	line[i] = '\0' ;
+	if( split()==NOMEM ) {
+		reset() ;
+		return NULL;			/* out of memory */
+	}
+	return (c==EOF && i==0) ? NULL : line ;
+}
+
+/* split: split line into fields */
+static int split( void )
+{
+	char *p, **newf ;
+	char *sepp; /* pointer to temporary separator character */
+	int sepc;   /* temporary separator character */
+
+	nfield = 0 ;
+	if( line[0]=='\0' )
+		return 0 ;
+	strcpy( sline, line ) ;
+	p = sline ;
+
+	do {
+		if( nfield>=maxfield ) {
+			maxfield *= 2;			/* double current size */
+			newf = (char**) realloc( field, 
+							maxfield * sizeof( field[0] )) ;
+			if( newf==NULL )
+				return NOMEM ;
+			field = newf ;
+		}
+		if( *p=='"' )
+			sepp = advquoted( ++p ) ;	/* skip initial quote */
+		else
+			sepp = p + strcspn( p, fieldsep ) ;
+		sepc = sepp[0] ;
+		sepp[0] = '\0' ;			/* terminate field */
+		field[nfield++] = p ;
+		p = sepp + 1 ;
+	} while( sepc==',' ) ;
+
+	return nfield ;
+}
+
+/* advquoted: quoted field; return pointer to next separator */
+static char *advquoted( char* p )
+{
+	int i, j ;
+
+	for( i=j=0; p[j]!='\0'; ++i, ++j ) {
+		if( p[j]=='"' && p[++j]!='"' ) {
+				/* copy up to next separator or \0 */
+			int k = strcspn( p+j, fieldsep ) ;
+			memmove( p+i, p+j, k ) ;
+			i += k ;
+			j += k ;
+			break ;
+		}
+		p[i] = p[j] ;
+	}
+	p[i] = '\0' ;
+	return p + j ;
+}
+
+/* csvfield:  return pointer to n-th field */
+char* csvfield( int n )
+{
+	if( n<0 || n>=nfield )
+		return NULL ;
+	return field[n] ;
+}
+
+/* csvnfield:  return number of fields */ 
+int csvnfield( void )
+{
+	return nfield ;
+}
+
+csv_t* csv_init( FILE *f )
+{
+	csv_t *rv = (csv_t*) malloc( sizeof( csv_t )) ;
+	rv->fin = f ;
+	reset( rv ) ;
+
+	return( rv ) ;
+}
+
+
+void kill( csv_t* s )
+{
+	reset( s ) ;
+	free( s ) ;
+}

lab08/lab8

+Yegeon Seo
+Lab 8
+
+Q1.
+
+Hide implementation details: Implementation that is hidden from the user so that one cannot affected from any change to code
+
+Choose a small orthogonal set of primitives: Limit code to a minimal having functions or methods performing same tasks and capabilities
+
+Don't reach behind the user's back: User interface should not invilve anything that the user is unaware of.
+
+Do the same thing the same way everywhere: User interface should be consistent across all platforms and functionality, along with the programming style.
+
+Q2.
+Code is unclear and has bad variable names. It can only have a line buffer with 200 characters because of the allocated memory, along with limited to 20 fields
+
+Q3.
+Programming style and variable names are more clear and easier to follow. Also includes comments.
+
+Q4.
+You cannot parse 2 different CSV files at the same time because of the way the program is written. You cannot read each line individually. 
+
+Q5.
+C++ implementation will not solve this problem. Although it will solve the issue of limited allocated memory in the original C program, it still doesn't handle errors empty fields
+
+Q6. 
+Yes, it does adhere to the guidelines for a good interface.
+
+