Start of vi.

1 files changed, 91 insertions, 0 deletions

diff --git a/toys/pending/vi.c b/toys/pending/vi.c
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+++ b/toys/pending/vi.c
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+/* vi.c - You can't spell "evil" without "vi".
+ *
+ * Copyright 2015 Rob Landley <rob@landley.net>
+ *
+ * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/vi.html
+
+USE_VI(NEWTOY(vi, "<1>1", TOYFLAG_USR|TOYFLAG_BIN))
+
+config VI
+  bool "vi"
+  default n
+  help
+    usage: vi FILE
+
+    Visual text editor. Predates the existence of standardized cursor keys,
+    so the controls are weird and historical.
+*/
+
+#define FOR_vi
+#include "toys.h"
+
+GLOBALS(
+  struct linestack *ls;
+  char *statline;
+)
+
+struct linestack {
+  long len, max;
+  char *line[];
+};
+
+// Insert one stack into another before position in old stack.
+// (Does not copy contents of strings, just shuffles index array contents.)
+void linestack_addstack(struct linestack **lls, struct linestack *throw,
+  long pos)
+{
+  struct linestack *catch = *lls;
+
+  if (CFG_TOYBOX_DEBUG)
+    if (pos > catch->len) error_exit("linestack_addstack past end.");
+
+  // Make a hole, allocating more space if necessary.
+  if (catch->len+throw->len >= catch->max) {
+    // New size rounded up to next multiple of 64, allocate and copy start.
+    catch->max = ((catch->len+throw->len)|63)+1;
+    *lls = xmalloc(sizeof(struct linestack)+catch->max*sizeof(char *));
+    memcpy(*lls, catch, sizeof(struct linestack)+pos*sizeof(char *));
+  }
+
+  // Copy end (into new allocation if necessary)
+  if (pos != catch->len)
+    memmove((*lls)->line+pos+throw->len, catch->line+pos,
+      (catch->len-pos)*sizeof(char *));
+
+  // Cleanup if we had to realloc.
+  if (catch != *lls) {
+    free(catch);
+    catch = *lls;
+  }
+
+  memcpy(catch->line+pos, throw->line, throw->len*sizeof(char *));
+  catch->len += throw->len;
+}
+
+void linestack_insert(struct linestack **lls, long pos, char *line)
+{
+  // alloca() was in 32V and Turbo C for DOS, but isn't in posix or c99.
+  // I'm not thrashing the heap for this, but this should work even if
+  // a broken compiler adds gratuitous padding.
+  struct {
+    struct linestack ls;
+    char *line;
+  } ls;
+
+  ls.ls.len = ls.ls.max = 1;
+  *ls.ls.line = line;
+  linestack_addstack(lls, &ls.ls, pos);
+}
+
+void vi_main(void)
+{
+  int i;
+
+  TT.ls = xzalloc(sizeof(struct linestack));
+
+  linestack_insert(&TT.ls, 0, "one");
+  linestack_insert(&TT.ls, 1, "two");
+  linestack_insert(&TT.ls, 2, "three");
+
+  for (i=0; i<TT.ls->len; i++) printf("%s\n", TT.ls->line[i]);  
+}