sed: fix range handling for sed -i. Closes 4069

function                                             old     new   delta
sed_main                                             606     618     +12
add_cmd                                             1099    1101      +2
process_files                                       2108    2099      -9
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 14/-9)               Total: 5 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 58 insertions, 31 deletions

diff --git a/editors/sed.c b/editors/sed.c
index 5c4e9cc3b..1552cf370 100644
--- a/editors/sed.c
+++ b/editors/sed.c
@@ -75,6 +75,13 @@
 #include "libbb.h"
 #include "xregex.h"
 
+#if 0
+# define dbg(...) bb_error_msg(__VA_ARGS__)
+#else
+# define dbg(...) ((void)0)
+#endif
+
+
 enum {
         OPT_in_place = 1 << 0,
 };
@@ -89,6 +96,7 @@ typedef struct sed_cmd_s {
         regex_t *end_match;     /* sed -e '/match/,/end_match/cmd' */
         regex_t *sub_match;     /* For 's/sub_match/string/' */
         int beg_line;           /* 'sed 1p'   0 == apply commands to all lines */
+        int beg_line_orig;      /* copy of the above, needed for -i */
         int end_line;           /* 'sed 1,3p' 0 == one line only. -1 = last line ($) */
 
         FILE *sw_file;          /* File (sw) command writes to, -1 for none. */
@@ -123,7 +131,7 @@ struct globals {
         regex_t *previous_regex_ptr;
 
         /* linked list of sed commands */
-        sed_cmd_t sed_cmd_head, *sed_cmd_tail;
+        sed_cmd_t *sed_cmd_head, **sed_cmd_tail;
 
         /* Linked list of append lines */
         llist_t *append_head;
@@ -148,7 +156,7 @@ struct BUG_G_too_big {
 #if ENABLE_FEATURE_CLEAN_UP
 static void sed_free_and_close_stuff(void)
 {
-        sed_cmd_t *sed_cmd = G.sed_cmd_head.next;
+        sed_cmd_t *sed_cmd = G.sed_cmd_head;
 
         llist_free(G.append_head, free);
 
@@ -599,6 +607,7 @@ static void add_cmd(const char *cmdstr)
 
                 /* first part (if present) is an address: either a '$', a number or a /regex/ */
                 cmdstr += get_address(cmdstr, &sed_cmd->beg_line, &sed_cmd->beg_match);
+                sed_cmd->beg_line_orig = sed_cmd->beg_line;
 
                 /* second part (if present) will begin with a comma */
                 if (*cmdstr == ',') {
@@ -630,8 +639,8 @@ static void add_cmd(const char *cmdstr)
                 cmdstr = parse_cmd_args(sed_cmd, cmdstr);
 
                 /* Add the command to the command array */
-                G.sed_cmd_tail->next = sed_cmd;
-                G.sed_cmd_tail = G.sed_cmd_tail->next;
+                *G.sed_cmd_tail = sed_cmd;
+                G.sed_cmd_tail = &sed_cmd->next;
         }
 
         /* If we glued multiple lines together, free the memory. */
@@ -777,7 +786,7 @@ static sed_cmd_t *branch_to(char *label)
 {
         sed_cmd_t *sed_cmd;
 
-        for (sed_cmd = G.sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) {
+        for (sed_cmd = G.sed_cmd_head; sed_cmd; sed_cmd = sed_cmd->next) {
                 if (sed_cmd->cmd == ':' && sed_cmd->string && !strcmp(sed_cmd->string, label)) {
                         return sed_cmd;
                 }
@@ -953,24 +962,24 @@ static void process_files(void)
 
         /* For every line, go through all the commands */
  restart:
-        for (sed_cmd = G.sed_cmd_head.next; sed_cmd; sed_cmd = sed_cmd->next) {
+        for (sed_cmd = G.sed_cmd_head; sed_cmd; sed_cmd = sed_cmd->next) {
                 int old_matched, matched;
 
                 old_matched = sed_cmd->in_match;
 
                 /* Determine if this command matches this line: */
 
-                //bb_error_msg("match1:%d", sed_cmd->in_match);
-                //bb_error_msg("match2:%d", (!sed_cmd->beg_line && !sed_cmd->end_line
-                //              && !sed_cmd->beg_match && !sed_cmd->end_match));
-                //bb_error_msg("match3:%d", (sed_cmd->beg_line > 0
-                //      && (sed_cmd->end_line || sed_cmd->end_match
-                //          ? (sed_cmd->beg_line <= linenum)
-                //          : (sed_cmd->beg_line == linenum)
-                //          )
-                //      )
-                //bb_error_msg("match4:%d", (beg_match(sed_cmd, pattern_space)));
-                //bb_error_msg("match5:%d", (sed_cmd->beg_line == -1 && next_line == NULL));
+                dbg("match1:%d", sed_cmd->in_match);
+                dbg("match2:%d", (!sed_cmd->beg_line && !sed_cmd->end_line
+                                && !sed_cmd->beg_match && !sed_cmd->end_match));
+                dbg("match3:%d", (sed_cmd->beg_line > 0
+                        && (sed_cmd->end_line || sed_cmd->end_match
+                            ? (sed_cmd->beg_line <= linenum)
+                            : (sed_cmd->beg_line == linenum)
+                            )
+                        ));
+                dbg("match4:%d", (beg_match(sed_cmd, pattern_space)));
+                dbg("match5:%d", (sed_cmd->beg_line == -1 && next_line == NULL));
 
                 /* Are we continuing a previous multi-line match? */
                 sed_cmd->in_match = sed_cmd->in_match
@@ -981,7 +990,14 @@ static void process_files(void)
                         || (sed_cmd->beg_line > 0
                             && (sed_cmd->end_line || sed_cmd->end_match
                                   /* note: even if end is numeric and is < linenum too,
-                                   * GNU sed matches! We match too */
+                                   * GNU sed matches! We match too, therefore we don't
+                                   * check here that linenum <= end.
+                                   * Example:
+                                   * printf '1\n2\n3\n4\n' | sed -n '1{N;N;d};1p;2,3p;3p;4p'
+                                   * first three input lines are deleted;
+                                   * 4th line is matched and printed
+                                   * by "2,3" (!) and by "4" ranges
+                                   */
                                 ? (sed_cmd->beg_line <= linenum)    /* N,end */
                                 : (sed_cmd->beg_line == linenum)    /* N */
                                 )
@@ -994,16 +1010,14 @@ static void process_files(void)
                 /* Snapshot the value */
                 matched = sed_cmd->in_match;
 
-                //bb_error_msg("cmd:'%c' matched:%d beg_line:%d end_line:%d linenum:%d",
-                //sed_cmd->cmd, matched, sed_cmd->beg_line, sed_cmd->end_line, linenum);
+                dbg("cmd:'%c' matched:%d beg_line:%d end_line:%d linenum:%d",
+                        sed_cmd->cmd, matched, sed_cmd->beg_line, sed_cmd->end_line, linenum);
 
                 /* Is this line the end of the current match? */
 
                 if (matched) {
                         /* once matched, "n,xxx" range is dead, disabling it */
-                        if (sed_cmd->beg_line > 0
-                         && !(option_mask32 & OPT_in_place) /* but not for -i */
-                        ) {
+                        if (sed_cmd->beg_line > 0) {
                                 sed_cmd->beg_line = -2;
                         }
                         sed_cmd->in_match = !(
@@ -1017,7 +1031,8 @@ static void process_files(void)
                                 /* or does this line matches our last address regex */
                                 || (sed_cmd->end_match && old_matched
                                      && (regexec(sed_cmd->end_match,
-                                                 pattern_space, 0, NULL, 0) == 0))
+                                                 pattern_space, 0, NULL, 0) == 0)
+                                )
                         );
                 }
 
@@ -1407,11 +1422,12 @@ int sed_main(int argc UNUSED_PARAM, char **argv)
                 add_input_file(stdin);
         } else {
                 int i;
-                FILE *file;
 
                 for (i = 0; argv[i]; i++) {
                         struct stat statbuf;
                         int nonstdoutfd;
+                        FILE *file;
+                        sed_cmd_t *sed_cmd;
 
                         if (LONE_DASH(argv[i]) && !(opt & OPT_in_place)) {
                                 add_input_file(stdin);
@@ -1423,11 +1439,13 @@ int sed_main(int argc UNUSED_PARAM, char **argv)
                                 status = EXIT_FAILURE;
                                 continue;
                         }
+                        add_input_file(file);
                         if (!(opt & OPT_in_place)) {
-                                add_input_file(file);
                                 continue;
                         }
 
+                        /* -i: process each FILE separately: */
+
                         G.outname = xasprintf("%sXXXXXX", argv[i]);
                         nonstdoutfd = xmkstemp(G.outname);
                         G.nonstdout = xfdopen_for_write(nonstdoutfd);
@@ -1438,15 +1456,20 @@ int sed_main(int argc UNUSED_PARAM, char **argv)
                          * but GNU sed 4.2.1 does not preserve them either */
                         fchmod(nonstdoutfd, statbuf.st_mode);
                         fchown(nonstdoutfd, statbuf.st_uid, statbuf.st_gid);
-                        add_input_file(file);
+
                         process_files();
                         fclose(G.nonstdout);
-
                         G.nonstdout = stdout;
+
                         /* unlink(argv[i]); */
                         xrename(G.outname, argv[i]);
                         free(G.outname);
                         G.outname = NULL;
+
+                        /* Re-enable disabled range matches */
+                        for (sed_cmd = G.sed_cmd_head; sed_cmd; sed_cmd = sed_cmd->next) {
+                                sed_cmd->beg_line = sed_cmd->beg_line_orig;
+                        }
                 }
                 /* Here, to handle "sed 'cmds' nonexistent_file" case we did:
                  * if (G.current_input_file >= G.input_file_count)
diff --git a/testsuite/sed.tests b/testsuite/sed.tests
index e9d0ed601..ba163e9e9 100755
--- a/testsuite/sed.tests
+++ b/testsuite/sed.tests
@@ -6,7 +6,7 @@
 
 . ./testing.sh
 
-# testing "description" "arguments" "result" "infile" "stdin"
+# testing "description" "commands" "result" "infile" "stdin"
 
 # Corner cases
 testing "sed no files (stdin)" 'sed ""' "hello\n" "" "hello\n"
@@ -225,7 +225,7 @@ testing "sed s/xxx/[/" "sed -e 's/xxx/[/'" "[\n" "" "xxx\n"
 #testing "sed -g (exhaustive)" "sed -e 's/[[:space:]]*/,/g'" ",1,2,3,4,5," \
 #       "" "12345"
 
-# testing "description" "arguments" "result" "infile" "stdin"
+# testing "description" "commands" "result" "infile" "stdin"
 
 testing "sed n command must reset 'substituted' bit" \
         "sed 's/1/x/;T;n;: next;s/3/y/;t quit;n;b next;: quit;q'" \
@@ -291,6 +291,10 @@ testing "sed understands \r" \
         "sed 's/r/\r/'" \
         "\rrr\n" "" "rrr\n"
 
-# testing "description" "arguments" "result" "infile" "stdin"
+testing "sed -i finishes ranges correctly" \
+        "sed '1,2d' -i input; echo \$?; cat input" \
+        "0\n3\n4\n" "1\n2\n3\n4\n" ""
+
+# testing "description" "commands" "result" "infile" "stdin"
 
 exit $FAILCOUNT