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-rw-r--r--6.5/Makefile13
-rw-r--r--6.5/getch.c23
-rw-r--r--6.5/getch.h2
-rw-r--r--6.5/hash.c115
-rw-r--r--6.5/hash.h18
-rw-r--r--6.5/main.c34
-rw-r--r--6.5/test.c5
-rw-r--r--6.5/word.c58
-rw-r--r--6.5/word.h3
9 files changed, 271 insertions, 0 deletions
diff --git a/6.5/Makefile b/6.5/Makefile
new file mode 100644
index 0000000..c99e8b9
--- /dev/null
+++ b/6.5/Makefile
@@ -0,0 +1,13 @@
+objects = main.o hash.o word.o getch.o
+CC = gcc
+CFLAGS = -Wvla -Wall -Wextra -Wstrict-prototypes -Wmissing-prototypes -fsanitize=address
+
+hash : $(objects)
+ $(CC) $(CFLAGS) -o hash $(objects)
+
+main.o : word.h hash.h
+word.o : getch.h
+
+.PHONY : clean
+clean:
+ rm hash $(objects)
diff --git a/6.5/getch.c b/6.5/getch.c
new file mode 100644
index 0000000..a473190
--- /dev/null
+++ b/6.5/getch.c
@@ -0,0 +1,23 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <error.h>
+#include <errno.h>
+#include "getch.h"
+
+#define MAXBUFF 100
+
+int gtop;
+char buff[MAXBUFF];
+
+char getch(void)
+{
+ return (gtop > 0) ? buff[--gtop] : getchar();
+}
+
+void ungetch(char c)
+{
+ if (gtop < MAXBUFF)
+ buff[gtop++] = c;
+ else
+ error(EXIT_FAILURE, ENOBUFS, "getch");
+}
diff --git a/6.5/getch.h b/6.5/getch.h
new file mode 100644
index 0000000..b0e086b
--- /dev/null
+++ b/6.5/getch.h
@@ -0,0 +1,2 @@
+char getch(void);
+void ungetch(char c);
diff --git a/6.5/hash.c b/6.5/hash.c
new file mode 100644
index 0000000..1e29bd7
--- /dev/null
+++ b/6.5/hash.c
@@ -0,0 +1,115 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include "hash.h"
+
+void nlfree(struct nlist *p);
+uint32_t hash(char *s, uint32_t hashsize);
+struct nlist *lookup(struct nlist *hashtab[], uint32_t hashsize, char *s);
+void pnl(struct nlist *np);
+
+uint32_t hash(char *s, uint32_t hashsize)
+{
+ uint32_t hashval;
+
+ for (hashval = 0; *s != '\0'; ++s)
+ hashval = *s + 31*hashval;
+
+ return hashval % hashsize;
+}
+
+struct nlist *lookup(struct nlist *hashtab[], uint32_t hashsize, char *s)
+{
+ struct nlist *np;
+
+ for (np = hashtab[hash(s, hashsize)]; np != NULL; np = np->next)
+ if (!strcmp(s, np->name))
+ return np;
+
+ return NULL;
+}
+
+struct nlist *install(struct nlist *hashtab[], uint32_t hashsize,
+ char *name, char *defn)
+{
+ struct nlist *np;
+ uint32_t hashval;
+
+ if ((np = lookup(hashtab, hashsize, name)) == NULL) {
+ np = (struct nlist *) malloc(sizeof(*np));
+ if (np == NULL || (np->name = strdup(name)) == NULL) {
+ nlfree(np);
+ return NULL;
+ }
+
+ hashval = hash(name, hashsize);
+ np->next = hashtab[hashval];
+ hashtab[hashval] = np;
+ } else {
+ free(np->defn);
+ }
+
+ if ((np->defn = strdup(defn)) == NULL) {
+ undef(hashtab, hashsize, name);
+ return NULL;
+ }
+
+ return np;
+}
+
+void undef(struct nlist *hashtab[], uint32_t hashsize, char *name)
+{
+ struct nlist *cur, *last;
+ uint32_t hashval = hash(name, hashsize);
+
+ for (cur = hashtab[hashval], last = NULL; cur !=NULL; last = cur,
+ cur = cur->next) {
+ if (!strcmp(cur->name, name)) {
+ if (last == NULL)
+ hashtab[hashval] = cur->next;
+ else
+ last->next = cur->next;
+
+ cur->next = NULL;
+ nlfree(cur);
+ return;
+ }
+ }
+}
+
+void pnl(struct nlist *np)
+{
+ if (np != NULL) {
+ pnl(np->next);
+ printf("%10s %s\n", np->name, np->defn);
+ }
+}
+
+void phashtab(struct nlist *hashtab[], int lim)
+{
+ int i;
+
+ for (i = 0; i < lim; ++i)
+ pnl(hashtab[i]);
+}
+
+void nlfree(struct nlist *p)
+{
+ if (p != NULL ) {
+ nlfree(p->next);
+ if (p->defn != NULL)
+ free(p->defn);
+ if (p->name != NULL)
+ free(p->name);
+ free(p);
+ }
+}
+
+void hashfree(struct nlist *hashtab[], int lim)
+{
+ int i;
+
+ for (i = 0; i < lim; ++i)
+ nlfree(hashtab[i]);
+}
diff --git a/6.5/hash.h b/6.5/hash.h
new file mode 100644
index 0000000..b32e0d4
--- /dev/null
+++ b/6.5/hash.h
@@ -0,0 +1,18 @@
+#include <stdint.h>
+
+#ifndef HASH_H
+
+struct nlist {
+ struct nlist *next;
+ char *name;
+ char *defn;
+};
+
+#define HASH_H
+#endif
+
+struct nlist *install(struct nlist *hashtab[], uint32_t hashsize,
+ char *name, char *defn);
+void undef(struct nlist *hashtab[], uint32_t hashsize, char *name);
+void phashtab(struct nlist *hastab[], int hashsize);
+void hashfree(struct nlist *hastab[], int hashsize);
diff --git a/6.5/main.c b/6.5/main.c
new file mode 100644
index 0000000..90bc87e
--- /dev/null
+++ b/6.5/main.c
@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "word.h"
+#include "hash.h"
+
+#define MAXWORD 100
+#define HASHSIZE 100
+
+struct nlist *hashtab[HASHSIZE];
+
+int main(void)
+{
+ char word[MAXWORD];
+ char *name;
+
+ while (getword(word, MAXWORD) != EOF) {
+ if (!strcmp(word, "#define")) {
+ getword(word, MAXWORD);
+ name = strdup(word);
+ getword(word, MAXWORD);
+ install(hashtab, HASHSIZE, name, word);
+ free(name);
+ } else if (!strcmp(word, "#undef")) {
+ getword(word, MAXWORD);
+ undef(hashtab, HASHSIZE, word);
+ }
+ }
+
+ phashtab(hashtab, HASHSIZE);
+ hashfree(hashtab, HASHSIZE);
+
+ return 0;
+}
diff --git a/6.5/test.c b/6.5/test.c
new file mode 100644
index 0000000..d905c15
--- /dev/null
+++ b/6.5/test.c
@@ -0,0 +1,5 @@
+#define sneed feed
+#define chuck seek
+#define based soy
+#define soy based
+#undef chuck
diff --git a/6.5/word.c b/6.5/word.c
new file mode 100644
index 0000000..045eaf7
--- /dev/null
+++ b/6.5/word.c
@@ -0,0 +1,58 @@
+// #include <stdio.h>
+// #include <stdlib.h>
+// #include <stdint.h>
+#include <ctype.h>
+// #include <string.h>
+// #include <error.h>
+// #include <errno.h>
+#include "getch.h"
+#include "word.h"
+
+// #define MAXBUFF 100
+//
+// uint32_t top;
+// char *wstack[MAXBUFF];
+
+char getword(char *word, int lim)
+{
+ char *w = word;
+
+ // if (top > 0)
+ // return *wstack[--top];
+
+ while (isblank(*w = getch()))
+ ;
+
+ if (isalpha(*w)) {
+ while ((isalnum(*++w = getch()) || *w == '_') && --lim > 0)
+ ;
+ ungetch(*w--);
+ } else if (*w == '#') {
+ --lim;
+ do {
+ *++w = getch();
+ } while (isalpha(*w) && --lim > 0);
+ ungetch(*w--);
+ }
+
+ *++w = '\0';
+ return word[0];
+}
+//
+// void ungetword(char *word)
+// {
+// if (top < MAXBUFF) {
+// if ((wstack[top++] = strdup(word)) == NULL)
+// error(EXIT_FAILURE, ENOBUFS, "ungetword");
+// } else {
+// error(EXIT_FAILURE, ENOBUFS, "ungetword");
+// }
+// }
+//
+// void wordfree(void)
+// {
+// uint32_t i;
+//
+// for (i = 0; i < top; ++i)
+// free(wstack[i]);
+// }
diff --git a/6.5/word.h b/6.5/word.h
new file mode 100644
index 0000000..fcd8240
--- /dev/null
+++ b/6.5/word.h
@@ -0,0 +1,3 @@
+char getword(char *word, int lim);
+// void ungetword(char *word);
+// void wordfree(void);