first commit

5 files changed, 431 insertions, 0 deletions

diff --git a/buff.c b/buff.c
new file mode 100644
index 0000000..91593bb
--- /dev/null
+++ b/buff.c
@@ -0,0 +1,170 @@
+#include "buff.h"
+
+line_t* __search_pos(int addr){
+  
+  int i;
+  line_t *cur = b_start;
+  for(i=1; i<addr; i++){
+    cur = cur -> next;
+  }
+  return cur;
+}
+
+int read_lines(FILE *fin){
+  
+  char buff[4096];
+  line_t *line;
+  size_t s;
+
+  while(feof(fin) == 0){
+    if (!fgets(buff, 4095, fin)) break;
+    s = strlen(buff) + 1;
+    line = malloc(sizeof(line_t));
+    line->s = s;
+    line->c = malloc(s * sizeof(char));
+    memcpy(line->c, buff, s);
+    line->next = NULL;
+    
+    if (b_start == NULL){
+      line->prev = NULL;
+      b_start = line;
+    }
+    else{
+      b_end->next = line;
+      line->prev = b_end;
+    }
+    b_end = line;
+    num += 1;
+  }
+  cur = b_end;
+  pos = num;
+}
+
+void print_cur_line(char lineno){
+  
+  if (!b_start){
+    printf("?\n");
+    return;
+  }
+  
+  if (lineno)
+    printf("%d\t", pos);
+  printf("%s", cur->c);
+}
+  
+void print_lines(char lineno){
+
+  line_t *p;
+  int i=0;
+  p = b_start;
+
+  
+  printf(">>> *** addr1: %d addr2: %d ***\n", addr1, addr2);
+  for (i=1; i<addr2; i++) p = p->next;
+  pos = i;
+  cur = p;
+  while(pos < addr1){
+    if (lineno)
+      printf("%d\t", pos);
+    printf("%s", cur->c);
+    cur = cur->next;
+    pos += 1;
+  }
+  if (lineno)
+    printf("%d\t", pos);
+  printf("%s", cur->c);
+  if (pos != num) {
+    pos += 1;
+    cur = cur -> next;
+  }
+}
+
+int move_to_line(int addr, char print){
+
+  if (addr > num)
+    return -1;
+  else if (addr >= 0){
+    pos = addr;
+    cur = __search_pos(pos);
+    if (print)
+      print_cur_line(0);
+  }
+  return pos;
+}
+
+void print_lineno(){
+  printf("%d\n", addr1);
+}
+
+int move_forward(int n){
+
+  if (pos + n > num){
+    printf("?\n");
+    return -1;
+  }
+  while(n-- >0){
+    cur = cur->next;
+  }
+  pos += n;
+  return 0;
+}
+
+int move_backward(int n){
+
+  if (pos - n < 1){
+    printf("?\n");
+    return -1;
+  }
+  while(n-- >0){
+    cur = cur->prev;
+  }
+  pos -= n;
+  return 0;
+}
+
+
+
+/* add lines after pos */
+void append_lines(){
+
+  char buff[4096];
+  int n,s;
+  line_t *first, *l, *last;
+  
+  n = 0;
+  first = last = NULL;
+  while(feof(stdin) == 0){
+    if (!fgets(buff, 4095, stdin)) break;
+    if (buff[0] == '.')
+      break;
+    s = strlen(buff) + 1;
+    l = malloc(sizeof(line_t));
+    l->c = malloc(s * sizeof(char));
+    memcpy(l->c, buff, s);
+    l->s = s;
+    if (first == NULL)
+      first = last = l;
+    else{
+      last -> next = l;
+      l->prev = last;
+      last = l;
+    }
+    n += 1;
+  }
+  if (addr1 == 0){
+    last->next = b_start;
+    b_start -> prev = last;
+    b_start = first;
+    move_to_line(n,0);
+  }
+  else{
+    last -> next = cur -> next;
+    cur->next = first;
+    first->prev = cur;
+    move_forward(n);
+  }
+}
+
+void insert_lines(){}
+
+void delete_lines(){}
diff --git a/buff.h b/buff.h
new file mode 100644
index 0000000..2d55c04
--- /dev/null
+++ b/buff.h
@@ -0,0 +1,34 @@
+#ifndef __BUFF_H__
+#define __BUFF_H__
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef struct line_t {
+  char *c;
+  unsigned int s;
+  struct line_t *prev;
+  struct line_t *next;
+} line_t;
+
+
+extern line_t *b_start;
+extern line_t *b_end;
+extern line_t *cur;
+extern unsigned int num;
+extern unsigned int pos;
+extern int addr1, addr2;
+
+int read_lines(FILE *);
+void print_lines(char);
+void print_cur_line(char);
+int move_to_line(int, char);
+void print_lineno();
+void append_lines();
+void insert_lines();
+void delete_lines();
+
+
+
+#endif /* __BUFF_H__ */
diff --git a/commands.txt b/commands.txt
new file mode 100644
index 0000000..24072c3
--- /dev/null
+++ b/commands.txt
@@ -0,0 +1,32 @@
+(.)a
+(.,.)c
+(.,.)d
+e [file]
+E [file]
+f [file]
+(1,$)g/RE/command list
+(1,$)G/RE/
+h
+H
+(.)i
+(.,.+1)j
+(.)kx
+(.,.)l
+(.,.)m_addr
+(.,.)n
+(.,.)p
+P
+q
+Q
+($)r
+(.,.)s/RE/replacement/flags
+(.,.)t_addr
+u
+(1,$)v/RE/command list
+(1,$)V/RE/
+(1,$)w [file]
+($)=
+!command
+(.+1) (NULL cmd)
+
+
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..0599575
--- /dev/null
+++ b/main.c
@@ -0,0 +1,186 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "buff.h"
+#include <ctype.h>
+
+line_t *b_start = NULL;
+line_t *b_end = NULL;
+line_t *cur = NULL;
+unsigned int num = 0;
+unsigned int pos = 0;
+/* addr1 is the lasr address, while addr2 is the previous one */
+int addr1, addr2;
+
+
+
+const char* skip_blank(const char **c){
+
+  while (isblank(**c)) (*c)++;
+  return *c;
+}
+
+
+int get_addr(const char **cmd){
+
+  int addr, n, got;
+  char sign = 0, comma = 0;
+  const char *c;
+  
+  addr1 = addr2 = -1;
+  c = *cmd;
+  while(*c){
+    c = skip_blank(&c);
+    n = 0;
+    got = 0;
+    if (isdigit(*c)){
+      while (isdigit(*c)){
+        got = 1;
+        n = n * 10 + *c - '0', c++;
+      }
+      if (got){
+        if (addr1 > -1 )
+          addr2 = addr1;
+        addr1 = n;
+      }
+    }
+    else {
+      switch(*c){
+      case '.':
+        if (addr1 > -1)
+          addr2 = addr1;
+        addr1 = pos;
+        break;
+      case '$':
+        if (addr1 > -1)
+          addr2 = addr1;
+        addr1 = num;
+        break;
+      case ',':
+        comma = 1;
+        if (addr1 < addr2){
+          *cmd = c;
+          return -1; 
+        }
+        break;
+      default:
+        goto check;
+      }
+      c++;
+    }
+  }
+ check:
+  *cmd = c;
+
+  if (addr1 == -1){
+    if (comma){
+      addr1 = num;
+      addr2 = 1;
+      return 2;
+    }
+    addr1 = addr2 = pos;
+    return 0;
+  }
+  if (addr2 == -1){
+    addr2 = pos;
+    return 1;
+  }
+  return 2;
+}
+
+
+void main_loop(){
+  
+  char *cmd;
+  int ret;
+  char p;
+  
+  cmd = malloc(256 * sizeof(char));
+  
+  while(1){
+    p = 0;
+    fgets(cmd, 255, stdin);
+    
+    ret = get_addr((const char **) &cmd);
+    
+    printf(">>> *** pos: %d address: %d ***\n", pos, ret);
+    if (ret) {
+      printf(">>>   *** addr1: %d, addr2= %d***\n", addr1, addr2);
+    }
+
+    switch(cmd[0]){
+    case 'i':
+      if (addr1 > -1)
+        move_to_line(addr1, 0);
+      insert_lines();
+      break;
+    case 'a':
+      if (addr1 > -1)
+        move_to_line(addr1, 0);
+      append_lines();
+      break;
+    case 'd':
+      delete_lines();
+      break;
+    case 'n': p = 1;
+    case 'p':
+      if (ret == 2)
+        if (addr1 < addr2){
+          printf("?\n");
+          break;
+        }
+        else
+          print_lines(p);
+      else  if (ret == 1) 
+        move_to_line(addr2, 1);
+      else if (ret == 0)
+        print_cur_line(p);
+      else if (ret == -1){
+        addr1 = num;
+        addr2 = 1;
+        move_to_line(addr2,0);
+        print_lines(p);
+      }
+      break;
+    case '\n':
+      if (addr1 > -1)
+        move_to_line(addr1, 1);
+      else
+        print_cur_line(p);
+      break;
+    case 'q':
+      exit(0);
+      break;
+    case '=':
+      if (addr1 == -1)
+        addr1 = num;
+      print_lineno();
+      break;
+    default:
+      printf(">>> **** unknown command: '%c'****\n", cmd[0])
+      ;
+    }
+  }
+}
+
+
+
+int main(int argc, char *argv[]){
+
+  FILE *fin;
+  
+  if (argc < 2){
+    printf("Usage: %s <filein>\n", argv[0]);
+    exit(1);
+  }
+  
+  if ((fin = fopen(argv[1], "r+"))){
+    read_lines(fin);
+  }
+  else{
+    printf("Error opening file %s\n", argv[1]);
+  }
+  
+  main_loop();
+}
+ 
diff --git a/notes.txt b/notes.txt
new file mode 100644
index 0000000..d00a80d
--- /dev/null
+++ b/notes.txt
@@ -0,0 +1,9 @@
+Implementation of an ed clone.
+
+Things to sort out:
+
+- buffering
+
+- regexp (use libc regexp (compat mode, to run also on *BSD))
+
+Target: 16KB