code review 5622058: cmd/dist: generate files for package runtime

src/cmd/dist/buf.c

 // Copyright 2012 The Go Authors.  All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 // Byte buffers and string vectors.
 
 #include "a.h"
 
 // binit prepares an uninitialized buffer for use.
 void
@@ skipping 81 matching lines @@
         bwrite(dst, src->p, src->len);
 }
 
 // bequal reports whether the buffers have the same content.
 bool
 bequal(Buf *s, Buf *t)
 {
         return s->len == t->len && xmemcmp(s->p, t->p, s->len) == 0;
 }
 
-// bsubst rewites b to replace the first occurrence of x with y.
+// bsubst rewites b to replace all occurrences of x with y.
 void
 bsubst(Buf *b, char *x, char *y)
 {
         char *p;
-        int nx, ny;
-
-        p = xstrstr(bstr(b), x);
-        if(p == nil)
-                return;
+        int nx, ny, pos;
+
         nx = xstrlen(x);
         ny = xstrlen(y);
-        if(nx != ny) {
-                if(nx < ny)
-                        bgrow(b, ny-nx);
-                xmemmove(p+ny, p+nx, (b->p+b->len)-(p+nx));
-        }
-        xmemmove(p, y, ny);
-        b->len += ny - nx;
+
+        pos = 0;
+        for(;;) {
+                p = xstrstr(bstr(b)+pos, x);
+                if(p == nil)
+                        break;
+                if(nx != ny) {
+                        if(nx < ny)
+                                bgrow(b, ny-nx);
+                        xmemmove(p+ny, p+nx, (b->p+b->len)-(p+nx));
+                }
+                xmemmove(p, y, ny);
+                pos = p+ny - b->p;
+                b->len += ny - nx;
+        }
 }
 
 // The invariant with the vectors is that v->p[0:v->len] is allocated
 // strings that are owned by the vector.  The data beyond v->len may
 // be garbage.
 
 // vinit prepares an uninitialized vector for use.
 void
 vinit(Vec *v)
 {
@@ skipping 131 matching lines @@
                 while(*p == ' ' || *p == '\t' || *p == '\r' || *p == '\n')
                         p++;
                 if(*p == '\0')
                         break;
                 start = p;
                 while(*p != ' ' && *p != '\t' && *p != '\r' && *p != '\n' && *p != '\0')
                         p++;
                 vaddn(v, start, p-start);
         }
 }