moved mdb.h and associated files int lib

4 files changed, 275 insertions, 0 deletions

diff --git a/src/lib/file.c b/src/lib/file.c
new file mode 100644
index 0000000..5011e45
--- /dev/null
+++ b/src/lib/file.c
@@ -0,0 +1,92 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "mdb.h"
+
+static char *getpair(int *c, FILE *fp);
+
+struct keytablist *readdb(char *filename)
+{
+  int len = 2;
+  struct keytablist *list = calloc(len, sizeof(struct keytablist));
+  FILE *fp = fopen(filename, "rb");
+  if (fp == NULL)
+    return list;
+
+  int c, i = 0, open = 0;
+  char *p;
+  while ((c = fgetc(fp)) != EOF) {
+    switch (c) {
+      case 250:
+        p = getpair(&c, fp);
+        if (p == NULL) {
+          fprintf(stderr, "missing pair closing byte!\n");
+          return NULL;
+        }
+        setkey(&list, &len, i, p);
+        free(p);
+        break;
+      case 251:
+        if (open == 1) {
+          fprintf(stderr, "missing object closing byte!\n");
+          return NULL;
+        }
+        open = 1;
+        break;
+      case 254:
+        open = 0;
+        i++;
+        break;
+      default:
+        fprintf(stderr, "Unknown byte: %d\n", c);
+        return NULL;
+    }
+  }
+  fclose(fp);
+  return list;
+}
+
+void writedb(char *filename, struct keytablist *list)
+{
+  FILE *fp = fopen(filename, "wb");
+  for (int i = 0; i < list[0].len; ++i) {
+    fprintf(fp, "\xfb");
+    int *indexes = getkeys(list, i);
+    for (int j = 0; indexes[j]; ++j) {
+      fprintf(fp, "\xfa%s:", list[i].tab[indexes[j]].key);
+      switch (list[i].tab[indexes[j]].flag) {
+        case 1:
+          fprintf(fp, "%.2lf\xfc", list[i].tab[indexes[j]].v.num);
+          break;
+        case 2:
+          fprintf(fp, "%s\xfc", list[i].tab[indexes[j]].v.b == 1 ? "true" : "false");
+          break;
+        case 3:
+          fprintf(fp, "%s\xfc", list[i].tab[indexes[j]].v.str);
+          break;
+      }
+    }
+    free(indexes);
+    fprintf(fp, "\xfe");
+  }
+  fclose(fp);
+}
+
+static char *getpair(int *c, FILE *fp)
+{
+  char *pair = calloc(3, sizeof(char));
+  int i = 0, len = 3;
+  while ((*c = fgetc(fp)) != 252 && *c != EOF) {
+    if (i >= len)
+      pair = realloc(pair, ++len * sizeof(char));
+    pair[i++] = *c;
+  }
+  pair = realloc(pair, ++len * sizeof(char));
+  pair[i] = '\0';
+  if (*c != 252) {
+    free(pair);
+    return NULL;
+  }
+  return pair;
+}
diff --git a/src/lib/keytab.c b/src/lib/keytab.c
new file mode 100644
index 0000000..61f94af
--- /dev/null
+++ b/src/lib/keytab.c
@@ -0,0 +1,113 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+#include "mdb.h"
+
+static const struct keytablist empty;
+
+static int hash(char *key);
+
+int *getkeys(struct keytablist *list, int id)
+{
+  int len = 2;
+  int *indexes = calloc(len, sizeof(int));
+  for (int i = 0, j = 0; i < TABLEN; ++i) {
+    if (j >= len) {
+      indexes = realloc(indexes, ++len * sizeof(int));
+      indexes[len - 1] = 0;
+    }
+    if (list[id].tab[i].key)
+      indexes[j++] = i;
+  }
+  return indexes;
+}
+
+struct keytab getkey(struct keytablist *list, int id, char *key)
+{
+  int idx = hash(key);
+  if (list[id].tab[idx].key == NULL)
+    return (struct keytab) { .key = NULL, .flag = 0, .v = 0 };
+
+  while (strcmp(list[id].tab[idx].key, key) && idx < TABLEN)
+    idx++;
+  if (idx >= TABLEN)
+    return (struct keytab) { .key = NULL, .flag = 0, .v = 0 };
+  return list[id].tab[idx];
+}
+
+int setkey(struct keytablist **list, int *len, int id, char *pair)
+{
+  if (id >= *len) {
+    *list = realloc(*list, (id + 1) * sizeof(struct keytablist));
+    for (int i = *len; i <= id; ++i)
+      (*list)[i] = empty;
+    *len = id + 1;
+    (*list)[0].len = *len;
+  }
+  char *tok = strtok(pair, ":");
+  char *key = calloc(strlen(tok) + 1, sizeof(char));
+  strcpy(key, tok);
+
+  tok = strtok(NULL, ":");
+  if (tok == NULL) {
+    fprintf(stderr, "Invalid key-value pair\n");
+    return 1;
+  }
+  union value v;
+  int flag;
+  if (isdigit(*tok)) {
+    flag = 1;
+    v.num = atof(tok);
+  } else if (!strcmp(tok, "true") || !strcmp(tok, "false")) {
+    flag = 2;
+    v.b = !strcmp(tok, "true");
+  } else {
+    flag = 3;
+    v.str = calloc(strlen(tok) + 1, sizeof(char));
+    strcpy(v.str, tok);
+  }
+
+  int idx = hash(key);
+  while ((*list)[id].tab[idx].key != NULL &&
+    strcmp((*list)[id].tab[idx].key, key) &&
+    idx < TABLEN) idx++;
+  if (idx >= TABLEN) {
+    fprintf(stderr, "No more room in table\n");
+    return 2;
+  }
+  if (!(*list)[id].tab[idx].key)
+    (*list)[id].tab[idx].key = key;
+  else
+    free(key);
+  (*list)[id].tab[idx].v = v;
+  (*list)[id].tab[idx].flag = flag;
+  return 0;
+}
+
+void delkey(struct keytablist *list, int id, char *key)
+{
+  int idx = hash(key);
+  while (strcmp(list[id].tab[idx].key, key) && idx < TABLEN)
+    idx++;
+  if (idx >= TABLEN) {
+    fprintf(stderr, "Invalid key: %s\n", key);
+    return;
+  }
+  free(list[id].tab[idx].key);
+  list[id].tab[idx].key = NULL;
+  if (list[id].tab[idx].flag == 3) {
+    free(list[id].tab[idx].v.str);
+    list[id].tab[idx].v.str = NULL;
+  }
+  list[id].tab[idx].flag = 0;
+}
+
+static int hash(char *key)
+{
+  unsigned long h = 5381;
+  for (int i = 0; i < strlen(key); ++i)
+    h = ((h << 5) + h) + key[i];
+  return h % TABLEN;
+}
diff --git a/src/lib/mdb.h b/src/lib/mdb.h
new file mode 100644
index 0000000..49f5903
--- /dev/null
+++ b/src/lib/mdb.h
@@ -0,0 +1,31 @@
+#ifndef MDB_H
+#define MDB_H
+
+#define TABLEN 1024
+
+union value {
+  char *str;
+  double num;
+  unsigned int b : 1;
+};
+
+struct keytab {
+  char *key;
+  int flag;
+  union value v;
+};
+
+struct keytablist {
+  int len;
+  struct keytab tab[TABLEN];
+};
+
+int *getkeys(struct keytablist *list, int id);
+struct keytab getkey(struct keytablist *list, int id, char *key);
+int setkey(struct keytablist **list, int *len, int id, char *pair);
+void delkey(struct keytablist *list, int id, char *key);
+
+struct keytablist *readdb(char *filename);
+void writedb(char *filename, struct keytablist *list);
+
+#endif
diff --git a/src/lib/test.c b/src/lib/test.c
new file mode 100644
index 0000000..5fb9f8b
--- /dev/null
+++ b/src/lib/test.c
@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#include "src/mdb.h"
+
+int main(int argc, char **argv)
+{
+  if (argc != 2)
+    exit(1);
+  char *filename = argv[1];
+  struct keytablist *list = readdb(filename);
+  if (list == NULL)
+    exit(2);
+
+  writedb(filename, list);
+  for (int i = 0; i < list[0].len; ++i) {
+    int *indexes = getkeys(list, i);
+    for (int j = 0; indexes[j]; ++j) {
+      printf("%s: ", list[i].tab[indexes[j]].key);
+      switch (list[i].tab[indexes[j]].flag) {
+        case 1:
+          printf("%.2lf\n", list[i].tab[indexes[j]].v.num);
+          break;
+        case 2:
+          printf("%d\n", list[i].tab[indexes[j]].v.b);
+          break;
+        case 3:
+          printf("%s\n", list[i].tab[indexes[j]].v.str);
+          break;
+      }
+      delkey(list, i, list[i].tab[indexes[j]].key);
+    }
+    free(indexes);
+  }
+
+  free(list);
+  exit(0);
+}