Move everything into a new repo.

1 files changed, 145 insertions, 0 deletions

diff --git a/userland/minibox/utilities/ed.c b/userland/minibox/utilities/ed.c
new file mode 100644
index 0000000..53270dc
--- /dev/null
+++ b/userland/minibox/utilities/ed.c
@@ -0,0 +1,145 @@
+// ed - edit text
+// ed [-p string] [-s] [file]
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#define COMMAND_MODE 0
+#define INPUT_MODE 1
+
+int mode = COMMAND_MODE;
+
+FILE *fp = NULL;
+FILE *mem_fp = NULL;
+int line_number = 1;
+
+int getline(char *buffer, size_t s) {
+  (void)s;
+  int i = 0;
+  char c;
+  for (;; i++) {
+    int rc = read(0, &c, 1);
+    assert(rc > 0);
+    printf("%c", c);
+    buffer[i] = c;
+    if ('\n' == c)
+      break;
+  }
+  buffer[i] = '\0';
+  return i;
+}
+
+void goto_line(void) {
+  char c;
+  fseek(mem_fp, 0, SEEK_SET);
+  int line = 1;
+  if (1 != line_number) {
+    // Goto line
+    for (; fread(&c, 1, 1, mem_fp);) {
+      if ('\n' == c)
+        line++;
+      if (line == line_number)
+        return;
+    }
+    printf("got to line: %d\n", line);
+    assert(0);
+  }
+}
+
+void read_line(void) {
+  char c;
+  goto_line();
+  for (; fread(&c, 1, 1, mem_fp);) {
+    if ('\n' == c)
+      break;
+    printf("%c", c);
+  }
+  printf("\n");
+}
+
+void goto_end_of_line(void) {
+  char c;
+  for (; fread(&c, 1, 1, mem_fp);) {
+    if ('\n' == c)
+      break;
+  }
+}
+
+void delete_line(void) {
+  long s = ftell(mem_fp);
+  printf("s: %d\n", s);
+  goto_end_of_line();
+  long end = ftell(mem_fp);
+  printf("end: %d\n", end);
+  long offset = end - s;
+  for (char buffer[4096];;) {
+    int rc = fread(buffer, 1, 100, mem_fp);
+    long reset = ftell(mem_fp);
+    if (0 == rc)
+      break;
+    fseek(mem_fp, s, SEEK_SET);
+    fwrite(buffer, 1, rc, mem_fp);
+    s += rc;
+    fseek(mem_fp, reset, SEEK_SET);
+  }
+}
+
+void read_command(void) {
+  char buffer[4096];
+  char *s = buffer;
+  getline(buffer, 4096);
+  int a = -1;
+  int rc = sscanf(buffer, "%d", &a);
+  if (0 < rc) {
+    line_number = a;
+  }
+  for (; isdigit(*s); s++)
+    ;
+  if (0 == strcmp(s, "i")) {
+    mode = INPUT_MODE;
+    return;
+  }
+  if (0 == strcmp(s, ".")) {
+    read_line();
+    return;
+  }
+  return;
+}
+
+void read_input(void) {
+  char buffer[4096];
+  int l = getline(buffer, 4096);
+  if (0 == strcmp(buffer, ".")) {
+    mode = COMMAND_MODE;
+    return;
+  }
+  goto_line();
+  delete_line();
+  goto_line();
+  assert(fwrite(buffer, l, 1, mem_fp));
+  return;
+}
+
+int ed_main(char argc, char **argv) {
+  if (argc < 2)
+    return 1;
+  char *buffer;
+  size_t size;
+  mem_fp = open_memstream(&buffer, &size);
+  assert(mem_fp);
+  fp = fopen(argv[1], "r");
+  assert(fp);
+  char r_buffer[4096];
+  for (int rc; (rc = fread(buffer, 1, 4096, fp));) {
+    fwrite(r_buffer, 1, rc, mem_fp);
+  }
+
+  for (;;) {
+    if (COMMAND_MODE == mode)
+      read_command();
+    else
+      read_input();
+  }
+  fclose(fp);
+  fclose(mem_fp);
+  return 0;
+}