Ticket #400: support multi-line search.

In order to use multiline search, select "Regular expression" mode and
use "\n" in the input line:

For example, if file contains lines

aaa
bbb

search string should be "aaa\nbbb".

As a side effect, non-printable ASCII symbols (\r, \t, etc) in the
search string can be used too.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>

lib/search/regex.c

@@ -902,7 +902,7 @@ mc_search__run_regex (mc_search_t * lc_mc_search, const void *user_data,
         {
             while (TRUE)
             {
-                int current_chr = '\n'; /* stop search symbol */
+                int current_chr = '\0'; /* stop search symbol */
 
                 ret = lc_mc_search->search_fn (user_data, current_pos, &current_chr);
 
@@ -921,7 +921,7 @@ mc_search__run_regex (mc_search_t * lc_mc_search, const void *user_data,
 
                 g_string_append_c (lc_mc_search->regex_buffer, (char) current_chr);
 
-                if ((char) current_chr == '\n' || virtual_pos > end_search)
+                if ((char) current_chr == '\0' || virtual_pos >= end_search)
                     break;
             }
         }
@@ -940,7 +940,7 @@ mc_search__run_regex (mc_search_t * lc_mc_search, const void *user_data,
 
                 current_pos++;
 
-                if (current_chr == '\n' || current_pos > end_search)
+                if (current_pos >= end_search)
                     break;
             }
 

tests/lib/search/Makefile.am

@@ -20,6 +20,7 @@ TESTS = \
 	hex_translate_to_regex \
 	regex_replace_esc_seq \
 	regex_process_escape_sequence \
+	regex_multiline_str \
 	translate_replace_glob_to_regex
 
 check_PROGRAMS = $(TESTS)
@@ -33,6 +34,9 @@ regex_replace_esc_seq_SOURCES = \
 regex_process_escape_sequence_SOURCES = \
 	regex_process_escape_sequence.c
 
+regex_multiline_str_SOURCES = \
+	regex_multiline_str.c
+
 translate_replace_glob_to_regex_SOURCES = \
 	translate_replace_glob_to_regex.c
 

tests/lib/search/regex_multiline_str.c

@@ -0,0 +1,155 @@
+/*
+   libmc - checks search functions
+
+   Copyright (C) 2022
+   Free Software Foundation, Inc.
+
+   Written by:
+   Steef Boerrigter <sxmboer@gmail.com>, 2022
+
+   This file is part of the Midnight Commander.
+
+   The Midnight Commander is free software: you can redistribute it
+   and/or modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the License,
+   or (at your option) any later version.
+
+   The Midnight Commander is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define TEST_SUITE_NAME "lib/search/search"
+
+#include "tests/mctest.h"
+
+#include "search.c"             /* for testing static functions */
+
+/* --------------------------------------------------------------------------------------------- */
+
+/* @DataSource("test_regex_multiline_str_ds") */
+/* *INDENT-OFF* */
+static const struct test_regex_multiline_str_ds
+{
+    const mc_search_type_t type;
+    const char *buffer;
+    const char *search_str;
+    const gboolean retval;
+} test_regex_multiline_str_ds[] =
+{
+    { /* 1. */
+        MC_SEARCH_T_NORMAL,
+        "abcdefgh",
+        "nope",
+        FALSE
+    },
+    { /* 2. */
+        MC_SEARCH_T_NORMAL,
+        "abcdefgh",
+        "def",
+        TRUE
+    },
+    { /* 3. */
+        MC_SEARCH_T_NORMAL,
+        "abcdefgh",
+        "z",
+        FALSE
+    },
+    { /* 4. */
+        MC_SEARCH_T_NORMAL,
+        "abcd	\tefgh",
+        "\t	",
+        TRUE
+    },
+    { /* 5. multiline */
+        MC_SEARCH_T_NORMAL,
+        "abcd\ne\nfgh",
+        "\ne\nf",
+        TRUE
+    },
+    { /* 6. */
+        MC_SEARCH_T_NORMAL,
+        "abcd\nefgh",
+        "d\ne",
+        TRUE
+    },
+    { /* 7. mc-4.8.28 fails this edge condition */
+        MC_SEARCH_T_NORMAL,
+        "abcdefgh\n",
+        "\n",
+        TRUE
+    },
+    { /* 8. mc-4.8.28 fails this edge condition */
+        MC_SEARCH_T_NORMAL,
+        "abcdefgh\n",
+        "\n\n",
+        FALSE
+    },
+    { /* 9. regex including newline */
+        MC_SEARCH_T_REGEX,
+        "abcd\nefgh",
+        "abc[c-e]\nef",
+        TRUE
+    },
+    { /* 10. regex's newline support */
+        MC_SEARCH_T_REGEX,
+        "abcd\nefgh",
+        "abc[c-e]\\nef",
+        TRUE
+    },
+};
+/* *INDENT-ON* */
+
+/* @Test(dataSource = "test_regex_multiline_str_ds") */
+/* *INDENT-OFF* */
+START_PARAMETRIZED_TEST (test_regex_multiline_str, test_regex_multiline_str_ds)
+/* *INDENT-ON* */
+{
+    /* given */
+    mc_search_t *s;
+    gboolean retval;
+
+    s = mc_search_new (data->buffer, NULL);
+    s->is_case_sensitive = FALSE;
+    s->search_type = data->type;
+
+    /* when */
+    retval = mc_search (data->search_str, DEFAULT_CHARSET, data->buffer, s->search_type);
+
+    /* then */
+    if (data->retval)
+    {
+        mctest_assert_true (retval);
+    }
+    else
+    {
+        mctest_assert_false (retval);
+    }
+
+    mc_search_free (s);
+}
+/* *INDENT-OFF* */
+END_PARAMETRIZED_TEST
+/* *INDENT-ON* */
+
+/* --------------------------------------------------------------------------------------------- */
+
+int
+main (void)
+{
+    TCase *tc_core;
+
+    tc_core = tcase_create ("Core");
+
+    /* Add new tests here: *************** */
+    mctest_add_parameterized_test (tc_core, test_regex_multiline_str, test_regex_multiline_str_ds);
+    /* *********************************** */
+
+    return mctest_run_all (tc_core);
+}
+
+/* --------------------------------------------------------------------------------------------- */