added center cmd to badroff

1 files changed, 28 insertions, 12 deletions

diff --git a/badroff.c b/badroff.c
index 8cf8961..323cba2 100644
--- a/badroff.c
+++ b/badroff.c
@@ -1,6 +1,8 @@
 #include <stdio.h>
 #include "sb.h"
 #include "buf.h"
+#include <string.h>
+#include <stdlib.h>
 
 typedef enum {
     false,
@@ -17,9 +19,8 @@ FILE* getfile(int argc, char** argv){
 FILE* in;
 buf* inbuf;
 
-int width;
-bool brk;
-
+int width = 80;
+bool brk = false; // not implemented
 
 size_t fillbuf(size_t len){ // returns real len
     int c;
@@ -29,24 +30,38 @@ size_t fillbuf(size_t len){ // returns real len
     return set;
 }
 
-size_t nlfill(){
+size_t chrfill(char chr){
     size_t line;
     size_t len = buflen(inbuf);
     char* str = peekstrbuf(inbuf, 0, len);
     for (line = 0; line < len; line++)
-        if (str[line] == '\n') return line+1;
-    for (int c = 0; c != '\n' && (c = fgetc(in)) != EOF; line++)
+        if (str[line] == chr) return line+1;
+    for (int c = 0; c != chr && (c = fgetc(in)) != EOF; line++)
         inschrbuf(inbuf, c);
     return line;
 }
 
-void cmd(void){
-    int n = nlfill();
-    popstrbuf(inbuf, n);
+char* center(char* text){
+    size_t len = strlen(text);
+    int max = width/2 + len/2; // excluding terminator
+    int min = max-len+1; // first index of *text
+    char* str = malloc(sizeof(char)*(max + 1));
+    str[max] = 0;
+    for (int i=0; i < min; i++) str[i] = ' ';
+    memcpy(str+min, text, len);
+    return str;
+}
+
+char* cmd(void){
+    char* dat = popstrbuf(inbuf, chrfill('\n'));
+    if (!strncmp(dat, "CT ", 3)){
+        return center(dat+3);
+    }
+    return "";
 }
 
 char* typeset(void){
-    return popstrbuf(inbuf, nlfill());
+    return popstrbuf(inbuf, chrfill('\n'));
 }
 
 char* line(void){
@@ -58,8 +73,9 @@ char* line(void){
     if (twobytes[0] == '.' && twobytes[1] == '\n') return typeset();
     if (twobytes[0] == '.') popchrbuf(inbuf);
     if (twobytes[0] == '.' && twobytes[1] != '.'){
-        cmd();
-        return line();
+        char* data = cmd();
+        if (data[0] != '\0') return data;
+        else return line();
     } else {
         return typeset();
     }