took the hashtable stuff out of segfault and put it into a library. good idea? dunno.

4 files changed, 176 insertions, 0 deletions

diff --git a/libhashtable/Makefile b/libhashtable/Makefile
new file mode 100644
index 0000000..7def401
--- /dev/null
+++ b/libhashtable/Makefile
@@ -0,0 +1,14 @@
+LDFLAGS=-lhashtable -Llibhashtable
+CFLAGS=-fpic -shared -pedantic -Wall
+TARGET=libhashtable.so
+
+all: $(TARGET)
+
+$(TARGET):
+	$(CC) $(CFLAGS) -o $(TARGET) libhashtable.c
+
+clean:
+	rm -f libhashtable.so
+
+install:
+	cp $(TARGET) /usr/local/lib/$(TARGET)
diff --git a/libhashtable/example.c b/libhashtable/example.c
new file mode 100644
index 0000000..614e440
--- /dev/null
+++ b/libhashtable/example.c
@@ -0,0 +1,24 @@
+#include <stdio.h>
+#include "libhashtable.h"
+
+extern char **environ;
+
+int main(int argc,char *argv[]) {
+ struct hashtable ht;
+ int i;
+ char *name;
+ char *value;
+ inittable(&ht);
+ for(i=0;environ[i];i++) {
+  name=strdup(environ[i]);
+  if((value=strchr(name,'=') )){
+   *value=0;
+   value++;
+  }
+  //printf("'%s' = '%s'\n",name,value);
+  ht_setkey(&ht,name,value);
+  free(name);
+ }
+ printf("PATH='%s'\n",ht_getvalue(&ht,"PATH"));
+ return 0;
+}
diff --git a/libhashtable/libhashtable.c b/libhashtable/libhashtable.c
new file mode 100644
index 0000000..c4ac2d3
--- /dev/null
+++ b/libhashtable/libhashtable.c
@@ -0,0 +1,115 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "hashtable.h"
+
+/*
+struct entry {//linked list node.
+ char *original;
+ char *target;
+ struct entry *prev;// doubly linked list. why?
+ struct entry *next;
+};
+
+struct hitem {//dunno why I don't just have this as a linked list.
+ struct entry *ll;
+};
+
+struct hashtable {
+ int kl;//number of keys in the table
+ struct hitem **bucket;
+ int *keys;
+};
+*/
+
+unsigned short hash(char *v) {//maybe use a seeded rand()? :) Thanks FreeArtMan
+ unsigned short h=0;
+ h=((*v)<<8)+(v?*(v+1):0);
+ srand(h);
+ return rand();
+}
+
+void inittable(struct hashtable *ht,int tsize) {
+ int i;
+ ht->bucket=malloc(sizeof(char *)*tsize);
+ ht->kl=0;
+ ht->keys=malloc(sizeof(int *)*tsize);
+ if(!ht) {
+  fprintf(stderr,"malloc error 6 in hash table.\n");
+  return;
+ }
+ for(i=0;i<tsize;i++) {
+  ht->bucket[i]=0;
+ }
+}
+
+//this seems too complicated.
+int ht_setkey(struct hashtable *ht,char *key,char *value) {
+ unsigned short h=hash(key);
+ struct entry *tmp;
+ int i;
+ for(i=0;i<ht->kl;i++) {
+  if(ht->keys[i]==h) break;
+ }
+ ht->keys[i]=h;
+ ht->kl=(ht->kl)>i+1?ht->kl:i+1;
+ if(!ht->bucket[h]) { //empty bucket!
+  //add this to the list of used buckets so we can easily
+  //use that list later for stuff.
+  if(!(ht->bucket[h]=malloc(sizeof(struct hitem)))) return 1; 
+  ht->bucket[h]->ll=0;
+  //we now have a valid hashtable entry and a NULL ll in it.
+  //don't bother with the new ll entry yet...
+ }
+ if((tmp=ll_getentry(ht->bucket[h]->ll,key)) != NULL) {
+  //we found this alias in the ll. now to replace the value
+  free(tmp->target);
+  if(!(tmp->target=strdup(value))) return 2;
+  return 0;
+ }
+ if(ht->bucket[h]->ll == NULL) {
+  if(!(ht->bucket[h]->ll=malloc(sizeof(struct entry)))) return 3;
+  ht->bucket[h]->ll->next=0;
+  ht->bucket[h]->ll->prev=0;
+  if(!(ht->bucket[h]->ll->original=strdup(key))) return 4;
+  if(!(ht->bucket[h]->ll->target=strdup(value))) return 5;
+ } else {
+  //go to the end and add another entry to the ll.
+  for(tmp=ht->bucket[h]->ll;tmp->next;tmp=tmp->next);
+  if(!(tmp->next=malloc(sizeof(struct entry)))) return 6;
+  tmp->next->prev=tmp;
+  tmp=tmp->next;
+  if(!(tmp->original=strdup(key))) return 7;
+  if(!(tmp->target=strdup(value))) return 8;
+  tmp->next=0;
+ }
+ return 0;
+}
+
+struct entry *ll_getentry(struct entry *start,char *msg) {
+ struct entry *m;
+ if(!msg) return NULL;
+ if(!start) return NULL;
+ for(m=start;m;m=m->next) {
+  if(!strncmp(msg,m->original,strlen(m->original)) && (msg[strlen(m->original)]==' ' || msg[strlen(m->original)] == 0)) {//this allows !c to get called when using !c2 if !c2 is defined after !c. >_>
+   return m;
+  }
+ }
+ return NULL;
+}
+
+struct entry *ht_getentry(struct hashtable *ht,char *key) {
+ unsigned short h=hash(key);
+ if(!ht->bucket[h]) return NULL;
+ return ht->bucket[h]->ll;
+}
+
+struct entry *ht_getnode(struct hashtable *ht,char *msg) {
+ return ll_getentry(ht_getentry(ht,msg),msg);
+}
+
+//you'll probably want to use me.
+char *ht_getvalue(struct hashtable *ht,char *msg) {
+ struct entry *tmp=ll_getentry(ht_getentry(ht,msg),msg);
+ return tmp?tmp->target:0;
+}
diff --git a/libhashtable/libhashtable.h b/libhashtable/libhashtable.h
new file mode 100644
index 0000000..7899124
--- /dev/null
+++ b/libhashtable/libhashtable.h
@@ -0,0 +1,23 @@
+struct entry {//linked list node.
+ char *original;
+ char *target;
+ struct entry *prev;// doubly linked list. why?
+ struct entry *next;
+};
+
+struct hitem {//dunno why I don't just have this as a linked list.
+ struct entry *ll;
+};
+
+struct hashtable {
+ int kl;//number of keys in the table
+ struct hitem **bucket;
+ int *keys;
+};
+unsigned short hash(char *v);//maybe use a seeded rand()? :) Thanks FreeArtMan
+void inittable(struct hashtable *ht);
+int ht_setkey(struct hashtable *ht,char *key,char *value);
+struct entry *ll_getentry(struct entry *start,char *msg);
+struct entry *ht_getentry(struct hashtable *ht,char *key);
+struct entry *ht_getnode(struct hashtable *ht,char *msg);
+char *ht_getvalue(struct hashtable *ht,char *msg);