Homework 06: str

homework06/Makefile

@@ -13,21 +13,27 @@ all:		$(TARGETS)
 # TODO: Add rules for libstr.a libstr.so
 #-------------------------------------------------------------------------------
 
-str.o:
+str.o: str.c
+	$(CC) $(CFLAGS) -c -o $@ $<
 
-libstr.so:
+libstr.so: str.o
+	$(LD) $(LDFLAGS) -shared -o $@ $<
 
-libstr.a:
+libstr.a: str.o
+	$(AR) $(ARFLAGS) $@ $<
 
 #-------------------------------------------------------------------------------
 # TODO: Add rules for trit.dynamic trit.static
 #-------------------------------------------------------------------------------
 
-trit.o:
+trit.o: trit.c
+	$(CC) $(CFLAGS) -c -o $@ $<
 
-trit.dynamic:
+trit.dynamic: trit.o
+	$(LD) $(LDFLAGS) -o $@ $< -lstr
 
-trit.static:
+trit.static: trit.o libstr.a
+	$(LD) -o $@ $< libstr.a
 
 #-------------------------------------------------------------------------------
 # DO NOT MODIFY BELOW

homework06/str.c

@@ -13,17 +13,27 @@
  * @param   s	    String to convert
  * @param   w	    Pointer to buffer that holds result of conversion
  **/
-void	str_lower(const char *s, char *w) {
-    // TODO
-}
+ void str_lower(const char *s, char *w) {
+     while (*s) {
+         *w = tolower(*s);
+         s++;
+         w++;
+     }
+     *w = '\0';
+ }
 
 /**
  * Convert string to uppercase.
  * @param   s	    String to convert
  * @param   w	    Pointer to buffer that holds result of conversion
  **/
-void	str_upper(const char *s, char *w) {
-    // TODO
+void str_upper(const char *s, char *w) {
+    while (*s) {
+        *w = toupper(*s);
+        s++;
+        w++;
+    }
+    *w = '\0';
 }
 
 /**
@@ -31,8 +41,22 @@ void	str_upper(const char *s, char *w) {
  * @param   s	    String to convert
  * @param   w	    Pointer to buffer that holds result of conversion
  **/
-void	str_title(const char *s, char *w) {
-    // TODO
+void str_title(const char *s, char *w) {
+    if (*s) {
+        *w = toupper(*s);
+        w++;
+        s++;
+        while (*s) {
+            if (!isalpha(*(s - 1))) {
+                *w = toupper(*s);
+            } else {
+                *w = tolower(*s);
+            }
+            s++;
+            w++;
+        }
+    }
+    *w = '\0';
 }
 
 /**
@@ -41,8 +65,38 @@ void	str_title(const char *s, char *w) {
  * @param   chars   Characters to strip (if NULL, then all whitespace)
  * @param   w	    Pointer to buffer that holds result of strip
  **/
-void	str_rstrip(const char *s, const char *chars, char *w) {
-    // TODO
+void str_rstrip(const char *s, const char *chars, char *w) {
+    bool strip_chars[256] = {0};
+
+    // Create the lookup table
+    if (chars == NULL) {
+        // If chars is NULL, strip whitespace
+        strip_chars[' '] = true;
+        strip_chars['\t'] = true;
+        strip_chars['\n'] = true;
+    } else {
+        // Otherwise, strip specified characters
+        while (*chars) {
+            strip_chars[(unsigned char)*chars] = true;
+            chars++;
+        }
+    }
+
+    // Copy s to w
+    const char *src = s;
+    char *dst = w;
+    while (*src) {
+        *dst++ = *src++;
+    }
+    *dst = '\0';
+
+    if (dst > w) {
+        dst--;
+        while (dst >= w && strip_chars[(unsigned char)*dst]) {
+            dst--;
+        }
+        *(dst + 1) = '\0';
+    }
 }
 
 /**
@@ -51,8 +105,24 @@ void	str_rstrip(const char *s, const char *chars, char *w) {
  * @param   chars   Characters to delete
  * @param   w	    Pointer to buffer that holds result of deletion
  **/
-void	str_delete(const char *s, const char *chars, char *w) {
-    // TODO
+void str_delete(const char *s, const char *chars, char *w) {
+    bool del_chars[256] = {0};
+
+    // Create lookup table
+    while (*chars) {
+        del_chars[(unsigned char)*chars] = true;
+        chars++;
+    }
+
+    // Copy non-deleted chars to w
+    while (*s) {
+        if (!del_chars[(unsigned char)*s]) {
+            *w = *s;
+            w++;
+        }
+        s++;
+    }
+    *w = '\0';
 }
 
 /**
@@ -62,8 +132,28 @@ void	str_delete(const char *s, const char *chars, char *w) {
  * @param   to      String with corresponding translation characters
  * @param   w	    Pointer to buffer that holds result of translation
  **/
-void	str_translate(const char *s, const char *from, const char *to, char *w) {
-    // TODO
+void str_translate(const char *s, const char *from, const char *to, char *w) {
+    unsigned char translate_table[256];
+    int i;
+
+    for (i = 0; i < 256; i++) {
+        translate_table[i] = i;
+    }
+
+    // Create the translation map
+    while (*from && *to) {
+        translate_table[(unsigned char)*from] = *to;
+        from++;
+        to++;
+    }
+
+    // Translate
+    while (*s) {
+        *w = translate_table[(unsigned char)*s];
+        s++;
+        w++;
+    }
+    *w = '\0';
 }
 
 /* vim: set sts=4 sw=4 ts=8 expandtab ft=c: */

reading08/grep.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+    // Your pattern matching implementation
+    return 0;
+}