Commit eff9fbd1 authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Fix an abstraction violation. 

Don't alias the insides of smartlist_t; that way lies madness.
parent 69b3e11e

src/or/consdiff.c

+9 −16
Original line number Diff line number Diff line
@@ -654,18 +654,19 @@ gen_ed_diff(const smartlist_t *cons1, const smartlist_t *cons2) 
  return NULL;

}



/** Apply the ed diff to the consensus and return a new consensus, also as a

 * line-based smartlist. Will return NULL if the ed diff is not properly

 * formatted.

/** Apply the ed diff, starting at <b>diff_starting_line</b>, to the consensus

 * and return a new consensus, also as a line-based smartlist. Will return

 * NULL if the ed diff is not properly formatted.

 */

STATIC smartlist_t *

apply_ed_diff(const smartlist_t *cons1, const smartlist_t *diff)

apply_ed_diff(const smartlist_t *cons1, const smartlist_t *diff,

              int diff_starting_line)

{

  int diff_len = smartlist_len(diff);

  int j = smartlist_len(cons1);

  smartlist_t *cons2 = smartlist_new();



  for (int i=0; i<diff_len; ++i) {

  for (int i=diff_starting_line; i<diff_len; ++i) {

    const char *diff_line = smartlist_get(diff, i);

    char *endptr1, *endptr2;
@@ -811,7 +812,7 @@ consdiff_gen_diff(const smartlist_t *cons1, const smartlist_t *cons2, 
  }



  /* See that the script actually produces what we want. */

  smartlist_t *ed_cons2 = apply_ed_diff(cons1, ed_diff);

  smartlist_t *ed_cons2 = apply_ed_diff(cons1, ed_diff, 0);

  if (!ed_cons2) {

    /* LCOV_EXCL_START -- impossible if diff generation is correct */

    log_warn(LD_BUG|LD_CONSDIFF, "Refusing to generate consensus diff because "
@@ -978,16 +979,8 @@ consdiff_apply_diff(const smartlist_t *cons1, 
  }



  /* Grab the ed diff and calculate the resulting consensus. */

  /* To avoid copying memory or iterating over all the elements, make a

   * read-only smartlist without the two header lines.

   */

  /* XXXX prop140 abstraction violation; never do this. */

  smartlist_t *ed_diff = tor_malloc(sizeof(smartlist_t));

  ed_diff->list = diff->list+2;

  ed_diff->num_used = diff->num_used-2;

  ed_diff->capacity = diff->capacity-2;

  cons2 = apply_ed_diff(cons1, ed_diff);

  tor_free(ed_diff);

  /* Skip the first two lines. */

  cons2 = apply_ed_diff(cons1, diff, 2);



  /* ed diff could not be applied - reason already logged by apply_ed_diff. */

  if (!cons2) {

src/or/consdiff.h

+2 −1
Original line number Diff line number Diff line
@@ -37,7 +37,8 @@ typedef struct smartlist_slice_t { 
STATIC smartlist_t *gen_ed_diff(const smartlist_t *cons1,

                                const smartlist_t *cons2);

STATIC smartlist_t *apply_ed_diff(const smartlist_t *cons1,

                                  const smartlist_t *diff);

                                  const smartlist_t *diff,

                                  int start_line);

STATIC void calc_changes(smartlist_slice_t *slice1, smartlist_slice_t *slice2,

                         bitarray_t *changed1, bitarray_t *changed2);

STATIC smartlist_slice_t *smartlist_slice(const smartlist_t *list,

src/test/test_consdiff.c

+15 −15
Original line number Diff line number Diff line
@@ -632,7 +632,7 @@ test_consdiff_apply_ed_diff(void *arg) 


  /* Command without range. */

  smartlist_add(diff, (char*)"a");

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  smartlist_clear(diff);

  expect_single_log_msg_containing("an ed command was missing a line number");
@@ -640,7 +640,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  /* Range without command. */

  smartlist_add(diff, (char*)"1");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("a line with no ed command was found");
@@ -649,7 +649,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  /* Range without end. */

  smartlist_add(diff, (char*)"1,");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("an ed command was missing a range "

                                   "end line number.");
@@ -659,7 +659,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  /* Incoherent ranges. */

  smartlist_add(diff, (char*)"1,1");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("an invalid range was found");
@@ -667,7 +667,7 @@ test_consdiff_apply_ed_diff(void *arg) 


  smartlist_add(diff, (char*)"3,2");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("an invalid range was found");
@@ -677,7 +677,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  smartlist_add(diff, (char*)"1d");

  smartlist_add(diff, (char*)"3d");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("its commands are not properly sorted");
@@ -686,7 +686,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  /* Script contains unrecognised commands longer than one char. */

  smartlist_add(diff, (char*)"1foo");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("an ed command longer than one char was "

                                   "found");
@@ -696,7 +696,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  /* Script contains unrecognised commands. */

  smartlist_add(diff, (char*)"1e");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("an unrecognised ed command was found");
@@ -706,7 +706,7 @@ test_consdiff_apply_ed_diff(void *arg) 
   * isn't. */

  smartlist_add(diff, (char*)"0a");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("it has an ed command that tries to "

                                   "insert zero lines.");
@@ -714,7 +714,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  /* Now it is followed by a ".", but it inserts zero lines. */

  smartlist_add(diff, (char*)".");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("it has an ed command that tries to "

                                   "insert zero lines.");
@@ -725,7 +725,7 @@ test_consdiff_apply_ed_diff(void *arg) 
  smartlist_add(diff, (char*)"0a");

  smartlist_add(diff, (char*)"hello");

  mock_clean_saved_logs();

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("lines to be inserted that don't end with "

                                   "a \".\".");
@@ -734,7 +734,7 @@ test_consdiff_apply_ed_diff(void *arg) 


  /* Test appending text, 'a'. */

  smartlist_split_string(diff, "3a:U:O:.:0a:V:.", ":", 0, 0);

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_NE, cons2);

  tt_int_op(8, OP_EQ, smartlist_len(cons2));

  tt_str_op("V", OP_EQ, smartlist_get(cons2, 0));
@@ -753,7 +753,7 @@ test_consdiff_apply_ed_diff(void *arg) 


  /* Test deleting text, 'd'. */

  smartlist_split_string(diff, "4d:1,2d", ":", 0, 0);

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_NE, cons2);

  tt_int_op(2, OP_EQ, smartlist_len(cons2));

  tt_str_op("C", OP_EQ, smartlist_get(cons2, 0));
@@ -766,7 +766,7 @@ test_consdiff_apply_ed_diff(void *arg) 


  /* Test changing text, 'c'. */

  smartlist_split_string(diff, "4c:T:X:.:1, 2c:M:.", ":", 0, 0);

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_NE, cons2);

  tt_int_op(5, OP_EQ, smartlist_len(cons2));

  tt_str_op("M", OP_EQ, smartlist_get(cons2, 0));
@@ -782,7 +782,7 @@ test_consdiff_apply_ed_diff(void *arg) 


  /* Test 'a', 'd' and 'c' together. */

  smartlist_split_string(diff, "4c:T:X:.:2d:0a:M:.", ":", 0, 0);

  cons2 = apply_ed_diff(cons1, diff);

  cons2 = apply_ed_diff(cons1, diff, 0);

  tt_ptr_op(NULL, OP_NE, cons2);

  tt_int_op(6, OP_EQ, smartlist_len(cons2));

  tt_str_op("M", OP_EQ, smartlist_get(cons2, 0));