output: --print-header to label columns

2 files changed, 104 insertions, 3 deletions

diff --git a/src/options.c b/src/options.c
index 16d6cf5..9220003 100644
--- a/src/options.c
+++ b/src/options.c
@@ -21,6 +21,7 @@ struct option long_options[] = {
     { "help", no_argument, 0, 0 },
     { "format-string", required_argument, 0, 0 },
     { "long-timestamp", no_argument, 0, 0 },
+    { "print-header", no_argument, 0, 0 },
     { "reverse-sort", no_argument, 0, 0 },
     { "show-hidden-entries", no_argument, 0, 0 },
     { "sort-by", required_argument, 0, 0 },
@@ -30,6 +31,7 @@ struct option long_options[] = {
 
 bool option_sort_reverse_order = false;
 enum esort_type option_sort_type = SORT_BY_SIZE;
+bool option_print_header = false;
 bool option_show_hidden_entries = false;
 bool option_timestamp_long = false;
 char *option_format_string = NULL;
@@ -55,6 +57,8 @@ void usage(char *executable) {
             "define columns to print, details below");
     fprintf(stderr, " %-25s %2s %10s  - %s\n", "--long-timestamp", "-t", "",
             "Print timestamp in long form yyyymmdd HH:MM:SS ZONE");
+    fprintf(stderr, " %-25s %2s %10s  - %s\n", "--print-header", "-H", "",
+            "Print a header above the columns");
     fprintf(stderr, " %-25s %2s %10s  - %s\n", "--reverse-sort", "", "",
             "Sort reversed");
     fprintf(stderr, " %-25s %2s %10s  - %s\n", "--show-hidden-entries", "-v", "",
@@ -108,6 +112,11 @@ void set_option(const char *option_name, char *option_argument) {
         return;
     }
 
+    if (strcmp("print-header", option_name) == 0) {
+        option_print_header = true;
+        return;
+    }
+
     if (strcmp("show-hidden-entries", option_name) == 0) {
         option_show_hidden_entries = true;
         return;
@@ -171,7 +180,7 @@ int parse_arguments(int argc, char **argv) {
 
     while(1) {
         index = 0;
-        c = getopt_long(argc, argv, "htv", long_options, &index);
+        c = getopt_long(argc, argv, "Hhtv", long_options, &index);
 
         if (c == -1) {
             break;
@@ -184,6 +193,9 @@ int parse_arguments(int argc, char **argv) {
             case 'h':
                 usage(exec_name);
                 exit(EXIT_SUCCESS);
+            case 'H':
+                option_print_header = true;
+                break;
             case 't':
                 option_timestamp_long = true;
                 break;
diff --git a/src/output.c b/src/output.c
index 04cafe7..5c68f17 100644
--- a/src/output.c
+++ b/src/output.c
@@ -25,6 +25,8 @@
 
 /* === DEFINITIONS === */
 
+#define DM_OUT_FORMAT_MAX_LEN 80
+
 #define out_vsep fputc('|', stdout)
 
 #define out_print_newline()  fputc('\n', stdout)
@@ -40,6 +42,7 @@ void out_print_time_by_option(struct list_node *ptr);
 void out_print_type(struct list_node *ptr);
 void out_print_user_name(struct list_node *ptr);
 
+void out_print_format_string_header(const char *format);
 
 /* === IMPLEMENTATION === */
 
@@ -174,7 +177,7 @@ inline void out_print_time(time_t tv) {
     tm = localtime(&tv);
     if (option_timestamp_long) {
         strftime(timestamp, sizeof(timestamp), "%Y%m%d %H:%M:%S %Z", tm);
-        printf(" %20s ", timestamp);
+        printf(" %22s ", timestamp);
     } else {
         strftime(timestamp, sizeof(timestamp), "%H:%M:%S", tm);
         printf(" %8s ", timestamp);
@@ -286,6 +289,83 @@ inline void out_print_permissions(struct list_node *ptr) {
     printf(" %4o ", mode);
 }
 
+inline void out_print_format_string_header(const char *format) {
+    size_t i=0, format_len=0;
+    char header[4096] = "";
+    char *pos = header;
+
+    if (format == NULL) return;
+    DBGTRC("DEBUG: format string: \"%s\"\n", format);
+
+
+    format_len = strnlen(format, DM_OUT_FORMAT_MAX_LEN);
+    /* Prevent buffer overflow, with the header string 32 byte buffer */
+    for (i=0; (i < format_len) && (strlen(header) < 4064); i++) {
+        switch (format[i]) {
+            case 'n':
+                sprintf(pos, " FILE ");
+                break;
+            case 's':
+                sprintf(pos, " %11s ", "SIZE   ");
+                break;
+            case 't':
+                if (option_timestamp_long) {
+                    sprintf(pos, " %c%-21s ", toupper(option_time_field), "TIME");
+                } else {
+                    sprintf(pos, " %c%-7s ", toupper(option_time_field), "TIME");
+                }
+                break;
+            case 'A':
+                if (option_timestamp_long) {
+                    sprintf(pos, " %-22s ", "ACCESS TIME");
+                } else {
+                    sprintf(pos, " %-8s ", "ATIME");
+                }
+                break;
+            case 'C':
+                if (option_timestamp_long) {
+                    sprintf(pos, " %-22s ", "CREATION TIME");
+                } else {
+                    sprintf(pos, " %-8s ", "CTIME");
+                }
+                break;
+            case 'M':
+                if (option_timestamp_long) {
+                    sprintf(pos, " %-22s ", "MODIFICATION TIME");
+                } else {
+                    sprintf(pos, " %-8s ", "MTIME");
+                }
+                break;
+            case 'T':
+                sprintf(pos, " %-12s ", "TYPE");
+                break;
+            case 'u':
+                sprintf(pos, " %-4s ", "UID");
+                break;
+            case 'g':
+                sprintf(pos, " %-4s ", "GID");
+                break;
+            case 'U':
+                sprintf(pos, " %-10s ", "USER");
+                break;
+            case 'G':
+                sprintf(pos, " %-10s ", "GROUP");
+                break;
+            case 'p':
+                sprintf(pos, " %-4s ", "PERM");
+                break;
+            case ' ':
+                break;
+            default:
+                LOGERR("WARNING: Invalid character 0x%02X ignoring it\n", format[i]);
+                break;
+        };
+        pos = &header[strlen(header)];
+    }
+    printf("%s\n", header);
+    fputc_width_x('-', strlen(header), stdout);
+    out_print_newline();
+}
 /* === END OF FORMATTING FUNCTIONS === */
 
 
@@ -305,6 +385,10 @@ void print_list(struct list_head *list) {
         }
     }
 
+    if (option_print_header) {
+        out_print_format_string_header("stn");
+    }
+
     ptr = lh->first;
     while (ptr != NULL) {
         out_print_size(ptr);
@@ -370,7 +454,12 @@ void print_list_formatted(const char *format, struct list_head *list) {
 
     /* Note: the maximum length needs to be adjusted if the strings
      * shall contain more complicated settings */
-    format_len = strnlen(format, 80);
+    format_len = strnlen(format, DM_OUT_FORMAT_MAX_LEN);
+    DBGTRC("DEBUG: format_len = %lu\n", format_len);
+
+    if (option_print_header) {
+        out_print_format_string_header(format);
+    }
 
     ptr = lh->first;
     while (ptr != NULL) {