[cmds] allow commands to set the prompt

Fixes #574 and #573

NEWS

@@ -9,6 +9,8 @@ lnav v0.8.5:
        programmatically manipulate filters.
      * The ":write-*" commands will now accept "/dev/clipboard" as a file name
        that writes to the system clipboard.
+     * The ":write-to" and ":write-raw-to" commands will now print out comments
+       and tags attached to the lines.
      * Added a ":redirect-to <path>" command to redirect command output to the
        given file.  This command is mostly useful in scripts where one might
        want to redirect all output from commands like ":echo" and ":write-to -"
@@ -24,6 +26,9 @@ lnav v0.8.5:
        strong fuzzy match.  If there are multiple matches, as would happen
        with ":dfil", readline's menu-complete behavior will be engaged and
        you can press TAB cycle through the options.
+     * When entering the ":comment" command for a line with a comment, the
+       command prompt will be filled in with the existing comment to make
+       editing easier.
 
      Fixes:
      * The ":write-json-to" command will now pass through JSON cells as their

src/lnav_commands.cc

@@ -541,6 +541,35 @@ static void json_write_row(yajl_gen handle, int row)
     }
 }
 
+static void write_line_to(FILE *outfile, attr_line_t &al)
+{
+    auto al_attrs = al.get_attrs();
+    struct line_range lr = find_string_attr_range(
+        al_attrs, &textview_curses::SA_ORIGINAL_LINE);
+    auto line_meta = find_string_attr(
+        al_attrs, &logline::L_META);
+
+    fwrite(lr.substr(al.get_string()),
+           1,
+           lr.sublen(al.get_string()),
+           outfile);
+    fwrite("\n", 1, 1, outfile);
+
+    if (line_meta != al_attrs.end()) {
+        auto bm = static_cast<const bookmark_metadata *>(line_meta->sa_value.sav_ptr);
+
+        if (!bm->bm_comment.empty()) {
+            fprintf(outfile, "  // %s\n", bm->bm_comment.c_str());
+        }
+        if (!bm->bm_tags.empty()) {
+            fprintf(outfile, "  -- %s\n",
+                    join(bm->bm_tags.begin(),
+                         bm->bm_tags.end(),
+                         " ").c_str());
+        }
+    }
+}
+
 static string com_save_to(exec_context &ec, string cmdline, vector<string> &args)
 {
     FILE *outfile = nullptr, *toclose = nullptr;
@@ -773,13 +802,7 @@ static string com_save_to(exec_context &ec, string cmdline, vector<string> &args
 
             tc->listview_value_for_rows(*tc, top, rows);
             for (auto &al : rows) {
-                struct line_range lr = find_string_attr_range(
-                    al.get_attrs(), &textview_curses::SA_ORIGINAL_LINE);
-                fwrite(lr.substr(al.get_string()),
-                       1,
-                       lr.sublen(al.get_string()),
-                       outfile);
-                fwrite("\n", 1, 1, outfile);
+                write_line_to(outfile, al);
 
                 line_count += 1;
             }
@@ -789,6 +812,7 @@ static string com_save_to(exec_context &ec, string cmdline, vector<string> &args
         }
     }
     else {
+        vector<attr_line_t> rows(1);
         bookmark_vector<vis_line_t>::iterator iter;
         size_t count = 0;
         string line;
@@ -797,8 +821,8 @@ static string com_save_to(exec_context &ec, string cmdline, vector<string> &args
             if (ec.ec_dry_run && count > 10) {
                 break;
             }
-            tc->grep_value_for_line(*iter, line);
-            fprintf(outfile, "%s\n", line.c_str());
+            tc->listview_value_for_rows(*tc, *iter, rows);
+            write_line_to(outfile, rows[0]);
 
             line_count += 1;
         }
@@ -1938,6 +1962,25 @@ static string com_comment(exec_context &ec, string cmdline, vector<string> &args
     return retval;
 }
 
+static string com_comment_prompt(exec_context &ec, const string &cmdline)
+{
+    textview_curses *tc = *lnav_data.ld_view_stack.top();
+
+    if (tc != &lnav_data.ld_views[LNV_LOG]) {
+        return "";
+    }
+    logfile_sub_source &lss = lnav_data.ld_log_source;
+    std::map<content_line_t, bookmark_metadata> &bm = lss.get_user_bookmark_metadata();
+
+    auto line_meta = bm.find(lss.at(tc->get_top()));
+
+    if (line_meta != bm.end() && !line_meta->second.bm_comment.empty()) {
+        return trim(cmdline) + " " + trim(line_meta->second.bm_comment);
+    }
+
+    return "";
+}
+
 static string com_clear_comment(exec_context &ec, string cmdline, vector<string> &args)
 {
     string retval;
@@ -4030,7 +4073,9 @@ readline_context::command_t STD_COMMANDS[] = {
             .with_summary("Attach a comment to the top log line")
             .with_parameter(help_text("text", "The comment text"))
             .with_example({"This is where it all went wrong"})
-            .with_tags({"metadata"})
+            .with_tags({"metadata"}),
+
+        com_comment_prompt,
     },
     {
         "clear-comment",
@@ -4050,7 +4095,7 @@ readline_context::command_t STD_COMMANDS[] = {
             .with_parameter(help_text("tag", "The tags to attach")
                                 .one_or_more())
             .with_example({"#BUG123 #needs-review"})
-            .with_tags({"metadata"})
+            .with_tags({"metadata"}),
     },
     {
         "untag",

src/log_format.cc

@@ -66,6 +66,7 @@ string_attr_type logline::L_FILE("file");
 string_attr_type logline::L_PARTITION("partition");
 string_attr_type logline::L_MODULE("module");
 string_attr_type logline::L_OPID("opid");
+string_attr_type logline::L_META("meta");
 
 external_log_format::mod_map_t external_log_format::MODULE_FORMATS;
 std::vector<external_log_format *> external_log_format::GRAPH_ORDERED_FORMATS;

src/log_format.hh

@@ -76,6 +76,7 @@ public:
     static string_attr_type L_PARTITION;
     static string_attr_type L_MODULE;
     static string_attr_type L_OPID;
+    static string_attr_type L_META;
 
     /**
      * Construct a logline object with the given values.

src/logfile_sub_source.cc

@@ -505,6 +505,14 @@ void logfile_sub_source::text_attrs_for_line(textview_curses &lv,
                 value_out.emplace_back(lr, &logline::L_PARTITION, &bm_iter->second);
             }
         }
+
+        auto bm_iter = this->lss_user_mark_metadata.find(this->at(vis_line_t(row)));
+
+        if (bm_iter != this->lss_user_mark_metadata.end()) {
+            lr.lr_start = 0;
+            lr.lr_end = -1;
+            value_out.emplace_back(lr, &logline::L_META, &bm_iter->second);
+        }
     }
 
     if (this->lss_token_file->is_time_adjusted()) {

src/readline_callbacks.cc

@@ -58,12 +58,24 @@ void rl_change(void *dummy, readline_curses *rc)
 
     switch (lnav_data.ld_mode) {
         case LNM_COMMAND: {
+            static string last_command;
+            static int generation = 0;
+
             string line = rc->get_line_buffer();
             vector<string> args;
             auto iter = lnav_commands.end();
 
             split_ws(line, args);
 
+            if (args.empty()) {
+                generation = 0;
+            } else if (args[0] != last_command) {
+                last_command = args[0];
+                generation = 0;
+            } else {
+                generation += 1;
+            }
+
             if (!args.empty()) {
                 iter = lnav_commands.find(args[0]);
             }
@@ -120,6 +132,16 @@ void rl_change(void *dummy, readline_curses *rc)
                     lnav_data.ld_example_source.replace_with(al);
                 }
 
+                if (cmd.c_prompt != nullptr && generation == 0 &&
+                    trim(line) == args[0]) {
+                    string new_prompt = cmd.c_prompt(
+                        lnav_data.ld_exec_context, line);
+
+                    if (!new_prompt.empty()) {
+                        rc->rewrite_line(line.length(), new_prompt);
+                    }
+                }
+
                 lnav_data.ld_bottom_source.grep_error("");
                 lnav_data.ld_status[LNS_BOTTOM].window_change();
             }

src/readline_curses.cc

@@ -176,7 +176,7 @@ static int recvall(int sock, char *buf, size_t len)
     off_t offset = 0;
 
     while (len > 0) {
-        int rc = recv(sock, &buf[offset], len, 0);
+        ssize_t rc = recv(sock, &buf[offset], len, 0);
 
         if (rc == -1) {
             switch (errno) {
@@ -600,12 +600,11 @@ void readline_curses::start()
                     char type[32];
 
                     msg[rc] = '\0';
-                    if (msg[0] == 'i') {
-                        const char *initial = &msg[2];
+                    if (sscanf(msg, "i:%d:%n", &rl_point, &prompt_start) == 1) {
+                        const char *initial = &msg[prompt_start];
 
                         rl_extend_line_buffer(strlen(initial) + 1);
                         strcpy(rl_line_buffer, initial);
-                        rl_point = 0;
                         rl_end = strlen(initial);
                         rl_redisplay();
                     }
@@ -923,7 +922,7 @@ void readline_curses::focus(int context, const char *prompt, const char *initial
     wmove(this->vc_window, this->get_actual_y(), this->vc_left);
     wclrtoeol(this->vc_window);
     if (initial != nullptr) {
-        snprintf(buffer, sizeof(buffer), "i:%s", initial);
+        snprintf(buffer, sizeof(buffer), "i:0:%s", initial);
         if (sendstring(this->rc_command_pipe[RCF_MASTER],
                        buffer,
                        strlen(buffer) + 1) == -1) {
@@ -932,6 +931,18 @@ void readline_curses::focus(int context, const char *prompt, const char *initial
     }
 }
 
+void readline_curses::rewrite_line(int pos, std::string value)
+{
+    char buffer[1024];
+
+    snprintf(buffer, sizeof(buffer), "i:%d:%s", pos, value.c_str());
+    if (sendstring(this->rc_command_pipe[RCF_MASTER],
+                   buffer,
+                   strlen(buffer) + 1) == -1) {
+        perror("focus: write failed");
+    }
+}
+
 void readline_curses::abort()
 {
     char buffer[1024];

src/readline_curses.hh

@@ -71,11 +71,14 @@ class readline_context {
 public:
     typedef std::string (*command_func_t)(exec_context &ec,
             std::string cmdline, std::vector<std::string> &args);
+    typedef std::string (*prompt_func_t)(exec_context &ec,
+        const std::string &cmdline);
     typedef struct _command_t {
         const char *c_name;
         command_func_t c_func;
 
         struct help_text c_help;
+        prompt_func_t c_prompt{nullptr};
 
         void operator=(command_func_t func) {
             this->c_name = "anon";
@@ -312,6 +315,8 @@ public:
 
     void focus(int context, const char *prompt, const char *initial = nullptr);
 
+    void rewrite_line(int pos, std::string value);
+
     readline_context *get_active_context() const {
         require(this->rc_active_context != -1);
 

src/session_data.cc

@@ -117,6 +117,8 @@ static bool bind_line(sqlite3 *db,
 
     char timestamp[64];
 
+    sqlite3_clear_bindings(stmt);
+
     sql_strftime(timestamp, sizeof(timestamp),
                  lf->original_line_time(line_iter), 'T');
     if (sqlite3_bind_text(stmt, 1,
@@ -499,9 +501,7 @@ static void load_time_bookmarks(void)
                     continue;
                 }
 
-                line_iter = lower_bound(lf->begin(),
-                                        lf->end(),
-                                        log_tv);
+                line_iter = lower_bound(lf->begin(), lf->end(), log_tv);
                 while (line_iter != lf->end()) {
                     struct timeval line_tv = line_iter->get_timeval();
 
@@ -523,12 +523,12 @@ static void load_time_bookmarks(void)
                             base_content_line + std::distance(lf->begin(), line_iter));
                         bool meta = false;
 
-                        if (part_name != NULL && part_name[0] != '\0') {
+                        if (part_name != nullptr && part_name[0] != '\0') {
                             lss.set_user_mark(&textview_curses::BM_META, line_cl);
                             bm_meta[line_cl].bm_name = part_name;
                             meta = true;
                         }
-                        if (comment != NULL && comment[0] != '\0') {
+                        if (comment != nullptr && comment[0] != '\0') {
                             lss.set_user_mark(&textview_curses::BM_META,
                                               line_cl);
                             bm_meta[line_cl].bm_comment = comment;

test/test_meta.sh

@@ -10,24 +10,27 @@ run_test ${lnav_test} -n \
     -c ":comment Hello, World!" \
     -c ":tag foo" \
     -c ":save-session" \
+    -c ":write-raw-to -" \
     ${test_dir}/logfile_access_log.0
 
 check_output ":tag did not work?" <<EOF
 192.168.202.254 - - [20/Jul/2009:22:59:26 +0000] "GET /vmw/cgi/tramp HTTP/1.0" 200 134 "-" "gPXE/0.9.7"
- + Hello, World!
- + #foo
+  // Hello, World!
+  -- #foo
 192.168.202.254 - - [20/Jul/2009:22:59:29 +0000] "GET /vmw/vSphere/default/vmkboot.gz HTTP/1.0" 404 46210 "-" "gPXE/0.9.7"
 192.168.202.254 - - [20/Jul/2009:22:59:29 +0000] "GET /vmw/vSphere/default/vmkernel.gz HTTP/1.0" 200 78929 "-" "gPXE/0.9.7"
 EOF
 
 run_test ${lnav_test} -n \
     -c ":load-session" \
+    -c ";UPDATE access_log SET log_mark = 1" \
+    -c ":write-to -" \
     ${test_dir}/logfile_access_log.0
 
 check_output "tag was not saved in session?" <<EOF
 192.168.202.254 - - [20/Jul/2009:22:59:26 +0000] "GET /vmw/cgi/tramp HTTP/1.0" 200 134 "-" "gPXE/0.9.7"
- + Hello, World!
- + #foo
+  // Hello, World!
+  -- #foo
 192.168.202.254 - - [20/Jul/2009:22:59:29 +0000] "GET /vmw/vSphere/default/vmkboot.gz HTTP/1.0" 404 46210 "-" "gPXE/0.9.7"
 192.168.202.254 - - [20/Jul/2009:22:59:29 +0000] "GET /vmw/vSphere/default/vmkernel.gz HTTP/1.0" 200 78929 "-" "gPXE/0.9.7"
 EOF