libsmartcols: add scols_table_print_range()

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libsmartcols/docs/libsmartcols-sections.txt b/libsmartcols/docs/libsmartcols-sections.txt
index 6289e3a2f194b92a7f2dd1cdc39e86c7b907cb27..4ac1291418975e22783549c0dc502dd0133b8618 100644 (file)
--- a/libsmartcols/docs/libsmartcols-sections.txt
+++ b/libsmartcols/docs/libsmartcols-sections.txt
@@ -143,6 +143,7 @@ scols_unref_table
 <FILE>table_print</FILE>
 scols_print_table
 scols_print_table_to_string
+scols_table_print_range
 </SECTION>
 
 <SECTION>

diff --git a/libsmartcols/samples/tree.c b/libsmartcols/samples/tree.c
index 52be7fbd57bbdc73bdff12d438a4160d131f7d66..d2afc4717d579009698c045377d1617ebe7f9297 100644 (file)
--- a/libsmartcols/samples/tree.c
+++ b/libsmartcols/samples/tree.c
@@ -142,13 +142,15 @@ static void add_lines(struct libscols_table *tb, const char *dirname)
 static void __attribute__((__noreturn__)) usage(FILE *out)
 {
        fprintf(out, " %s [options] [<dir> ...]\n\n", program_invocation_short_name);
-       fputs(" -c, --csv            display a csv-like output\n", out);
-       fputs(" -i, --ascii          use ascii characters only\n", out);
-       fputs(" -l, --list           use list format output\n", out);
-       fputs(" -n, --noheadings     don't print headings\n", out);
-       fputs(" -p, --pairs          use key=\"value\" output format\n", out);
-       fputs(" -J, --json           use JSON output format\n", out);
-       fputs(" -r, --raw            use raw output format\n", out);
+       fputs(" -c, --csv               display a csv-like output\n", out);
+       fputs(" -i, --ascii             use ascii characters only\n", out);
+       fputs(" -l, --list              use list format output\n", out);
+       fputs(" -n, --noheadings        don't print headings\n", out);
+       fputs(" -p, --pairs             use key=\"value\" output format\n", out);
+       fputs(" -J, --json              use JSON output format\n", out);
+       fputs(" -r, --raw               use raw output format\n", out);
+       fputs(" -S, --range-start <n>   first line to print\n", out);
+       fputs(" -E, --range-end <n>     last line to print\n", out);
 
        exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
 }
@@ -156,7 +158,8 @@ static void __attribute__((__noreturn__)) usage(FILE *out)
 int main(int argc, char *argv[])
 {
        struct libscols_table *tb;
-       int c, notree = 0;
+       int c, notree = 0, nstart = -1, nend = -1;
+
 
        static const struct option longopts[] = {
                { "ascii",      0, 0, 'i' },
@@ -166,7 +169,8 @@ int main(int argc, char *argv[])
                { "pairs",      0, 0, 'p' },
                { "json",       0, 0, 'J' },
                { "raw",        0, 0, 'r' },
-
+               { "range-start",1, 0, 'S' },
+               { "range-end",  1, 0, 'E' },
                { NULL, 0, 0, 0 },
        };
 
@@ -178,7 +182,7 @@ int main(int argc, char *argv[])
        if (!tb)
                err(EXIT_FAILURE, "faild to create output table");
 
-       while((c = getopt_long(argc, argv, "ciJlnpr", longopts, NULL)) != -1) {
+       while((c = getopt_long(argc, argv, "ciJlnprS:E:", longopts, NULL)) != -1) {
                switch(c) {
                case 'c':
                        scols_table_set_column_separator(tb, ",");
@@ -206,6 +210,12 @@ int main(int argc, char *argv[])
                        scols_table_enable_raw(tb, 1);
                        notree = 1;
                        break;
+               case 'S':
+                       nstart = strtos32_or_err(optarg, "failed to parse range start") - 1;
+                       break;
+               case 'E':
+                       nend = strtos32_or_err(optarg, "failed to parse range end") - 1;
+                       break;
                default:
                        usage(stderr);
                }
@@ -219,8 +229,21 @@ int main(int argc, char *argv[])
        else while (optind < argc)
                add_lines(tb, argv[optind++]);
 
-       scols_print_table(tb);
-       scols_unref_table(tb);
+       if (nstart >= 0 || nend >= 0) {
+               /* print subset */
+               struct libscols_line *start = NULL, *end = NULL;
+
+               if (nstart >= 0)
+                       start = scols_table_get_line(tb, nstart);
+               if (nend >= 0)
+                       end = scols_table_get_line(tb, nend);
 
+               if (start || end)
+                       scols_table_print_range(tb, start, end);
+       } else
+               /* print all table */
+               scols_print_table(tb);
+
+       scols_unref_table(tb);
        return EXIT_SUCCESS;
 }

diff --git a/libsmartcols/src/libsmartcols.h.in b/libsmartcols/src/libsmartcols.h.in
index 213d50af2da59d2f74cde712a3df9f894965be93..5f87d965f055fa22e81bb670b5578641e06a2152 100644 (file)
--- a/libsmartcols/src/libsmartcols.h.in
+++ b/libsmartcols/src/libsmartcols.h.in
@@ -246,6 +246,10 @@ extern int scols_sort_table(struct libscols_table *tb, struct libscols_column *c
 extern int scols_print_table(struct libscols_table *tb);
 extern int scols_print_table_to_string(struct libscols_table *tb, char **data);
 
+extern int scols_table_print_range(    struct libscols_table *tb,
+                                       struct libscols_line *start,
+                                       struct libscols_line *end);
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/libsmartcols/src/libsmartcols.sym b/libsmartcols/src/libsmartcols.sym
index 1a5505c474c55f1e09f20776119672d6bc264568..250c06d6dd3644679057b6c94f01c9cc653744a7 100644 (file)
--- a/libsmartcols/src/libsmartcols.sym
+++ b/libsmartcols/src/libsmartcols.sym
@@ -132,4 +132,5 @@ global:
        scols_table_get_title;
        scols_cell_get_flags;
        scols_cell_set_flags;
+       scols_table_print_range;
 } SMARTCOLS_2.27;

diff --git a/libsmartcols/src/table.c b/libsmartcols/src/table.c
index f91526bbd5604fe3c620789393e2e57b14fb522e..fdbc7cd3f091cb953198562e9eeec55f70b8fd7b 100644 (file)
--- a/libsmartcols/src/table.c
+++ b/libsmartcols/src/table.c
@@ -572,13 +572,7 @@ err:
  * @tb: table
  * @n: column number (0..N)
  *
- * This is a shortcut for
- *
- *   ln = scols_new_line();
- *   scols_line_set_....(cl, ...);
- *   scols_table_add_line(tb, ln);
- *
- * Returns: a newly allocate line
+ * Returns: a line or NULL
  */
 struct libscols_line *scols_table_get_line(struct libscols_table *tb,
                                           size_t n)

diff --git a/libsmartcols/src/table_print.c b/libsmartcols/src/table_print.c
index 06fcabe9f1a6a6363415fda9f3d59eea37eb037f..d8965726e74fc0cbda157b218e010c1c0650e5f4 100644 (file)
--- a/libsmartcols/src/table_print.c
+++ b/libsmartcols/src/table_print.c
@@ -801,24 +801,39 @@ static int print_header(struct libscols_table *tb, struct libscols_buffer *buf)
        return rc;
 }
 
-static int print_table(struct libscols_table *tb, struct libscols_buffer *buf)
+static int print_range(        struct libscols_table *tb,
+                       struct libscols_buffer *buf,
+                       struct libscols_iter *itr,
+                       struct libscols_line *end)
 {
        int rc = 0;
        struct libscols_line *ln;
-       struct libscols_iter itr;
 
        assert(tb);
 
-       scols_reset_iter(&itr, SCOLS_ITER_FORWARD);
-       while (rc == 0 && scols_table_next_line(tb, &itr, &ln) == 0) {
+       while (rc == 0 && scols_table_next_line(tb, itr, &ln) == 0) {
+
                fput_line_open(tb);
                rc = print_line(tb, ln, buf);
-               fput_line_close(tb, scols_iter_is_last(&itr));
+               fput_line_close(tb, scols_iter_is_last(itr));
+
+               if (end && ln == end)
+                       break;
        }
 
        return rc;
+
 }
 
+static int print_table(struct libscols_table *tb, struct libscols_buffer *buf)
+{
+       struct libscols_iter itr;
+
+       scols_reset_iter(&itr, SCOLS_ITER_FORWARD);
+       return print_range(tb, buf, &itr, NULL);
+}
+
+
 static int print_tree_line(struct libscols_table *tb,
                           struct libscols_line *ln,
                           struct libscols_buffer *buf,
@@ -1202,33 +1217,14 @@ static size_t strlen_line(struct libscols_line *ln)
        return sz;
 }
 
-
-
-/**
- * scols_print_table:
- * @tb: table
- *
- * Prints the table to the output stream.
- *
- * Returns: 0, a negative value in case of an error.
- */
-int scols_print_table(struct libscols_table *tb)
+static int initialize_printting(struct libscols_table *tb, struct libscols_buffer **buf)
 {
-       int rc = 0;
        size_t bufsz, extra_bufsz = 0;
        struct libscols_line *ln;
        struct libscols_iter itr;
-       struct libscols_buffer *buf;
-
-       if (!tb)
-               return -EINVAL;
-
-       DBG(TAB, ul_debugobj(tb, "printing"));
+       int rc;
 
-       if (list_empty(&tb->tb_lines)) {
-               DBG(TAB, ul_debugobj(tb, "ignore -- epmty table"));
-               return 0;
-       }
+       DBG(TAB, ul_debugobj(tb, "initialize printting"));
 
        if (!tb->symbols)
                scols_table_set_symbols(tb, NULL);      /* use default */
@@ -1262,7 +1258,9 @@ int scols_print_table(struct libscols_table *tb)
        case SCOLS_FMT_EXPORT:
        {
                struct libscols_column *cl;
+
                scols_reset_iter(&itr, SCOLS_ITER_FORWARD);
+
                while (rc == 0 && scols_table_next_column(tb, &itr, &cl) == 0) {
                        if (scols_column_is_hidden(cl))
                                continue;
@@ -1275,7 +1273,6 @@ int scols_print_table(struct libscols_table *tb)
                break;
        }
 
-
        /*
         * Enlarge buffer if necessary, the buffer should be large enough to
         * store line data and tree ascii art (or another decoration).
@@ -1287,16 +1284,87 @@ int scols_print_table(struct libscols_table *tb)
                        bufsz = sz;
        }
 
-       buf = new_buffer(bufsz + 1);    /* data + space for \0 */
-       if (!buf)
+       *buf = new_buffer(bufsz + 1);   /* data + space for \0 */
+       if (!*buf)
                return -ENOMEM;
 
        if (tb->format == SCOLS_FMT_HUMAN) {
-               rc = recount_widths(tb, buf);
+               rc = recount_widths(tb, *buf);
                if (rc != 0)
-                       goto done;
+                       goto err;
        }
 
+       return 0;
+err:
+       free_buffer(*buf);
+       return rc;
+}
+
+/**
+ * scola_table_print_range:
+ * @tb: table
+ * @start: first printed line or NULL to print from the beggin of the table
+ * @end: last printed line or NULL to print all from start.
+ *
+ * Returns: 0, a negative value in case of an error.
+ */
+int scols_table_print_range(   struct libscols_table *tb,
+                               struct libscols_line *start,
+                               struct libscols_line *end)
+{
+       struct libscols_buffer *buf;
+       struct libscols_iter itr;
+       int rc;
+
+       if (scols_table_is_tree(tb))
+               return -EINVAL;
+
+       DBG(TAB, ul_debugobj(tb, "printing range"));
+
+       rc = initialize_printting(tb, &buf);
+       if (rc)
+               return rc;
+
+       if (start) {
+               itr.direction = SCOLS_ITER_FORWARD;
+               itr.head = &tb->tb_lines;
+               itr.p = &start->ln_lines;
+       } else
+               scols_reset_iter(&itr, SCOLS_ITER_FORWARD);
+
+       rc = print_range(tb, buf, &itr, end);
+
+       free_buffer(buf);
+       return 0;
+}
+
+/**
+ * scols_print_table:
+ * @tb: table
+ *
+ * Prints the table to the output stream.
+ *
+ * Returns: 0, a negative value in case of an error.
+ */
+int scols_print_table(struct libscols_table *tb)
+{
+       int rc = 0;
+       struct libscols_buffer *buf;
+
+       if (!tb)
+               return -EINVAL;
+
+       DBG(TAB, ul_debugobj(tb, "printing"));
+
+       if (list_empty(&tb->tb_lines)) {
+               DBG(TAB, ul_debugobj(tb, "ignore -- epmty table"));
+               return 0;
+       }
+
+       rc = initialize_printting(tb, &buf);
+       if (rc)
+               return rc;
+
        fput_table_open(tb);
 
        if (tb->format == SCOLS_FMT_HUMAN)