Add splint checking to Makefile. Rewrite programs to pass lint.

Add an error handling mechanism to common, and rename it support.h.

README

@@ -10,3 +10,6 @@
     than Busybox.
 
     I recommend compiling these statically.
+
+    If SPLint is available, 'make check' can perform static analysis of
+    all available programs.

src/Makefile

@@ -4,7 +4,7 @@ CC	= cc
 CFLAGS	= -Wall -O2
 LDFLAGS = -static
 LDLIBS	=
-PREFIX = /usr/local/
+PREFIX = usr/local
 DESTDIR = 
 BIN = echo yes true false cat
 
@@ -18,14 +18,15 @@ false:
 cat: cat.c
 
 install: all
-	install -Dm0775 ${BIN} ${DESTDIR}${PREFIX}bin
+	install -Dm0755 ${BIN} ${DESTDIR}/${PREFIX}/bin
 
-clean: 
-	rm echo true  yes false cat
+clean: all
+	rm ${BIN} *.o
+
+check: 
+	splint +checks +posix-strict-lib +showsummary +forcehints +showscan +showsourceloc +toctou +its4low +its4moderate +its4risky +its4veryrisky +its4mostrisky +bufferoverflow *.c *.h
 
 .SUFFIXES: .c .o
 .c.o:
 	${CC} ${CFLAGS} ${LDFLAGS} -c $<
 
-:
-	echo hello

src/cat.c

@@ -1,28 +1,22 @@
-/* cat.c -- provides a routine to output the contents of the named files in either a buffered or unbuffered fashion. */
-/* Accepts the following parameters:                                                                                 */
-/*     -u: Output should be unbuffered.                                                                              */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
 
-/* Returns the following values: */
-/*     0: All files were printed successfully. */
-/*     1: One or more files could not be opened. */
-   
+#include "support.h"
 
-#include "common.h"
 
-/* If mode is set to zero, return a null pointer and print characters directly. Otherwise, return a pointer to a buffer containing */
-/* the contents of the file pointed to by fp. The size of the new buffer is stored in the int pointed to by bufsize.               */
 char *cat(FILE *fp, const int mode, long unsigned *bufsize)
     {
     char c;
-    
+    static long unsigned int i, finalbuflen, tmpbuflen;
+    char *arr, *tmparr, *finalarr;
+    tmpbuflen = 4096;
+
     if(!mode)
 	{
-	static long unsigned int i, finalbuflen, tmpbuflen;
-	tmpbuflen = 4096;
-	char *arr = malloc(tmpbuflen);
-	char *tmparr = 0;
-	char *finalarr = 0;
-	
+	arr = malloc(tmpbuflen);
+	tmparr = finalarr = 0;
+		
 	for(i = 0, finalbuflen = 0; (c = fgetc(fp)) != EOF; i++, finalbuflen++)
 	    {
 	    if(i >= tmpbuflen)
@@ -57,14 +51,14 @@ char *cat(FILE *fp, const int mode, long unsigned *bufsize)
 
 int main(int argc, char **argv)
     {
+    long unsigned int i, upresence, fppresence, buflen, newbuflen;
     char *buf, *newbuf, *tmpbuf;
-    long unsigned int i, upresence, fppresence;
-    i = upresence = fppresence = 0;
-    long unsigned int buflen, newbuflen;
-    buflen = newbuflen = 0;
     FILE *fp;
-    fp = 0;
+    
+    i = upresence = fppresence = buflen = newbuflen = 0;
     buf = newbuf = tmpbuf = 0;
+    fp = 0;
+
     
     if((upresence = (getopt(argc, argv, ":u") == 'u')))
 	{

src/common.h

@@ -1,30 +0,0 @@
-#include <iso646.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/stat.h>
-
-/* arrccat -- function to copy arr2len bytes from arr2 to the arr1len'th position of arr1. returns *newarr, and stores the length */
-/* of newarr[] in arr1len (that's why it needs to be a pointer to arr1len and not just a long unsigned integer).                  */
-char *arrccat(char *arr1, char *arr2, size_t *arr1len, size_t arr2len)
-    {
-    char *newarr;
-    unsigned int i, i2;
-    newarr = malloc(*arr1len+arr2len);
-    i = i2 = 0;
-
-    for(i = 0; i < *arr1len; i++)
-	{
-	newarr[i] = arr1[i];
-	}
-
-    for(i2 = 0; i2 < arr2len; i2++, i++)
-	{
-	newarr[i] = arr2[i2];
-	}
-    
-    *arr1len = *arr1len+arr2len;
-
-    return newarr;
-    }

src/echo.c

@@ -1,4 +1,4 @@
-#include "common.h"
+#include "support.h"
 
 int main(int argc, char **argv)
     {

src/support.h

@@ -0,0 +1,84 @@
+#include <iso646.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+enum {
+    UNKNOWN_FAIL = 1,
+    MALLOC_FAIL,
+    NEEDARG_FAIL,
+    FOPEN_FAIL,
+    WRITE_FAIL
+    };
+
+
+/* arrccat -- function to copy arr2len bytes from arr2 to the arr1len'th position of arr1. returns *newarr, and stores the length */
+/* of newarr[] in arr1len (that's why it needs to be a pointer to arr1len and not just a long unsigned integer).                  */
+char *arrccat(char *arr1, char *arr2, size_t *arr1len, size_t arr2len)
+    {
+    char *newarr;
+    unsigned int i, i2;
+    newarr = malloc(*arr1len+arr2len);
+    i = i2 = 0;
+
+    for(i = 0; i < *arr1len; i++)
+	{
+	newarr[i] = arr1[i];
+	}
+
+    for(i2 = 0; i2 < arr2len; i2++, i++)
+	{
+	newarr[i] = arr2[i2];
+	}
+    
+    *arr1len = *arr1len+arr2len;
+
+    return newarr;
+    }
+
+/* Condition should be one of the above enum'd strings. Info is optional; it can just be NULL when irrelevant. */
+void throw(long unsigned int condition, void *info)
+    {
+    switch(condition)
+	{
+	case UNKNOWN_FAIL: printf("unknown failure\n");
+	    exit(UNKNOWN_FAIL);
+	case MALLOC_FAIL: printf("malloc failure\n");
+	    exit(MALLOC_FAIL);
+	case NEEDARG_FAIL: printf("usage: %s\n", (char *) info);
+	    exit(NEEDARG_FAIL);
+	case FOPEN_FAIL: printf("failed to open: %s\n", (char *) info);
+	    exit(FOPEN_FAIL);
+	case WRITE_FAIL: printf("failed to write: %s\n", (char *) info);
+	    exit(WRITE_FAIL);
+	default: printf("You shouldn't be seeing this.\nSomething is very wrong.\n");
+	    exit(-256);
+	}
+    }
+
+/* mastrcat -- improved string concat function. returns a pointer to the first element in a buffer containing the strings str1 */
+/* and str2 joined end-to-end. */ 
+char *mastrcat(char *str1, char *str2)
+    {
+    unsigned long int nbi, stri, nbsize;
+    char *nbuf;
+    nbi = stri = 0;
+    nbsize = (strlen(str1) + strlen(str2));
+    nbuf = malloc(nbsize);
+
+    for(stri = 0; str1[stri] != '\0'; nbi++, stri++)
+        {
+        nbuf[nbi] = str1[stri];
+        }
+
+    for(stri = 0; str2[stri] != '\0'; nbi++, stri++)
+        {
+        nbuf[nbi] = str2[stri];
+        }
+    
+    return nbuf;
+        }
+

src/true.c

@@ -1,4 +1,4 @@
-#include "common.h"
+#include "support.h"
 
 int main(int argc, char **argv)
     {

src/yes.c

@@ -1,4 +1,4 @@
-#include "common.h"
+#include "support.h"
 
 int main(int argc, char **argv)
     {