[breakpoint] add :enable-breakpoint and :disable-breakpoint

Author: tstack

NEWS.md

@@ -99,6 +99,9 @@ Features:
     focused line in the LOG view.  Once breakpoints have
     been added, you can press `F7`/`F8` to move to the
     previous/next log message that matches a breakpoint.
+  - The `:disable-breakpoint` and `:enable-breakpoint`
+    commands have been added to allow disabling a
+    breakpoint without deleting it.
   - If the log format specifies source file/line fields
     and a breakpoint is set, a red bullet point will be
     inserted to signify the presence of a breakpoint.

src/cmds.breakpoints.cc

@@ -303,6 +303,205 @@ com_toggle_breakpoint(exec_context& ec,
     return com_breakpoint(ec, cmdline, args);
 }
 
+static std::string
+schema_id_for_point(const std::string& point,
+                    logfile_sub_source* lss,
+                    textview_curses* tc)
+{
+    static const auto POINT_RE
+        = lnav::pcre2pp::code::from_const(R"(^(?:([^:\s]+):)?([^:]+):(\d+)$)");
+    thread_local auto md = lnav::pcre2pp::match_data::unitialized();
+
+    if (POINT_RE.capture_from(point).into(md).found_p()) {
+        std::string format_name;
+
+        if (md[1]) {
+            format_name = md[1]->to_string();
+        } else if (lss != nullptr) {
+            auto line_pair = lss->find_line_with_file(tc->get_selection());
+            if (line_pair) {
+                format_name = line_pair->first->get_format_name().to_string();
+            }
+        }
+
+        if (!format_name.empty()) {
+            auto h = hasher();
+            h.update(format_name);
+            h.update(md[2].value());
+            h.update(md[3].value());
+            return h.to_string();
+        }
+    }
+
+    return {};
+}
+
+static Result<std::string, lnav::console::user_message>
+com_disable_breakpoint(exec_context& ec,
+                       std::string cmdline,
+                       std::vector<std::string>& args)
+{
+    static const intern_string_t SRC = intern_string::lookup("point");
+    std::string retval;
+
+    auto pat = trim(remaining_args(cmdline, args));
+    shlex lexer(pat);
+    auto split_args_res = lexer.split(ec.create_resolver());
+    if (split_args_res.isErr()) {
+        auto split_err = split_args_res.unwrapErr();
+        auto um
+            = lnav::console::user_message::error(
+                  "unable to parse breakpoint")
+                  .with_reason(split_err.se_error.te_msg)
+                  .with_snippet(lnav::console::snippet::from(
+                      SRC, lexer.to_attr_line(split_err.se_error)))
+                  .move();
+
+        return Err(um);
+    }
+
+    auto* tc = *lnav_data.ld_view_stack.top();
+    auto* lss = dynamic_cast<logfile_sub_source*>(tc->get_sub_source());
+    auto& bps = lnav_data.ld_log_source.get_breakpoints();
+    auto split_args = split_args_res.unwrap()
+        | lnav::itertools::map([](const auto& elem) { return elem.se_value; });
+
+    if (ec.ec_dry_run) {
+        return Ok(retval);
+    }
+
+    std::vector<std::string> disabled;
+
+    if (split_args.empty()) {
+        if (lss == nullptr) {
+            return ec.make_error(
+                "A breakpoint definition must be given if the "
+                "top view is not the LOG view");
+        }
+
+        auto schema_id
+            = get_current_line_schema_id(*lss, tc->get_selection().value());
+        if (schema_id.empty()) {
+            return ec.make_error(
+                "Could not determine schema for the current line");
+        }
+
+        auto it = bps.find(schema_id);
+        if (it == bps.end()) {
+            return ec.make_error("No breakpoint set for the current line");
+        }
+
+        it->second.bp_enabled = false;
+        disabled.emplace_back(it->second.bp_description);
+    }
+
+    for (const auto& point : split_args) {
+        auto schema_id = schema_id_for_point(point, lss, tc);
+        if (schema_id.empty()) {
+            return ec.make_error("Invalid breakpoint: {}", point);
+        }
+
+        auto it = bps.find(schema_id);
+        if (it == bps.end()) {
+            return ec.make_error("No breakpoint matching: {}", point);
+        }
+
+        it->second.bp_enabled = false;
+        disabled.emplace_back(it->second.bp_description);
+    }
+
+    if (!disabled.empty()) {
+        retval = fmt::format(FMT_STRING("info: disabled breakpoints -- {}"),
+                             fmt::join(disabled, ", "));
+    }
+
+    return Ok(retval);
+}
+
+static Result<std::string, lnav::console::user_message>
+com_enable_breakpoint(exec_context& ec,
+                      std::string cmdline,
+                      std::vector<std::string>& args)
+{
+    static const intern_string_t SRC = intern_string::lookup("point");
+    std::string retval;
+
+    auto pat = trim(remaining_args(cmdline, args));
+    shlex lexer(pat);
+    auto split_args_res = lexer.split(ec.create_resolver());
+    if (split_args_res.isErr()) {
+        auto split_err = split_args_res.unwrapErr();
+        auto um
+            = lnav::console::user_message::error(
+                  "unable to parse breakpoint")
+                  .with_reason(split_err.se_error.te_msg)
+                  .with_snippet(lnav::console::snippet::from(
+                      SRC, lexer.to_attr_line(split_err.se_error)))
+                  .move();
+
+        return Err(um);
+    }
+
+    auto* tc = *lnav_data.ld_view_stack.top();
+    auto* lss = dynamic_cast<logfile_sub_source*>(tc->get_sub_source());
+    auto& bps = lnav_data.ld_log_source.get_breakpoints();
+    auto split_args = split_args_res.unwrap()
+        | lnav::itertools::map([](const auto& elem) { return elem.se_value; });
+
+    std::vector<std::string> enabled;
+
+    if (split_args.empty()) {
+        if (lss == nullptr) {
+            return ec.make_error(
+                "A breakpoint definition must be given if the "
+                "top view is not the LOG view");
+        }
+
+        auto schema_id
+            = get_current_line_schema_id(*lss, tc->get_selection().value());
+        if (schema_id.empty()) {
+            return ec.make_error(
+                "Could not determine schema for the current line");
+        }
+
+        auto it = bps.find(schema_id);
+        if (it != bps.end()) {
+            if (ec.ec_dry_run) {
+                return Ok(retval);
+            }
+            it->second.bp_enabled = true;
+            enabled.emplace_back(it->second.bp_description);
+        } else {
+            return com_breakpoint(ec, cmdline, args);
+        }
+    }
+
+    for (const auto& point : split_args) {
+        auto schema_id = schema_id_for_point(point, lss, tc);
+        if (schema_id.empty()) {
+            return ec.make_error("Invalid breakpoint: {}", point);
+        }
+
+        auto it = bps.find(schema_id);
+        if (it != bps.end()) {
+            if (ec.ec_dry_run) {
+                continue;
+            }
+            it->second.bp_enabled = true;
+            enabled.emplace_back(it->second.bp_description);
+        } else {
+            return com_breakpoint(ec, cmdline, args);
+        }
+    }
+
+    if (!enabled.empty()) {
+        retval = fmt::format(FMT_STRING("info: enabled breakpoints -- {}"),
+                             fmt::join(enabled, ", "));
+    }
+
+    return Ok(retval);
+}
+
 static readline_context::command_t BREAKPOINT_COMMANDS[] = {
     {
         "breakpoint",
@@ -346,6 +545,36 @@ static readline_context::command_t BREAKPOINT_COMMANDS[] = {
                     .one_or_more())
             .with_example({"To clear all breakpoints", "*"}),
     },
+    {
+        "disable-breakpoint",
+        com_disable_breakpoint,
+        help_text(":disable-breakpoint")
+            .with_summary(
+                "Disable a breakpoint for the given "
+                "[<format>:]<file>:<line> tuples "
+                "or the current line")
+            .with_parameter(
+                help_text("point")
+                    .with_summary(
+                        "The file and line number of the breakpoint")
+                    .with_format(help_parameter_format_t::HPF_BREAKPOINT)
+                    .zero_or_more()),
+    },
+    {
+        "enable-breakpoint",
+        com_enable_breakpoint,
+        help_text(":enable-breakpoint")
+            .with_summary(
+                "Enable or create a breakpoint for the given "
+                "[<format>:]<file>:<line> tuples "
+                "or the current line")
+            .with_parameter(
+                help_text("point")
+                    .with_summary(
+                        "The file and line number of the breakpoint")
+                    .with_format(help_parameter_format_t::HPF_BREAKPOINT)
+                    .zero_or_more()),
+    },
 };
 
 void

src/internals/cmd-ref.rst

@@ -528,6 +528,20 @@
 ----
 
 
+.. _disable_breakpoint:
+
+:disable-breakpoint *point*
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+  Disable a breakpoint for the given [<format>:]<file>:<line> tuples or the current line
+
+  **Parameters**
+    * **point** --- The file and line number of the breakpoint
+
+
+----
+
+
 .. _disable_filter:
 
 :disable-filter *pattern*
@@ -588,6 +602,20 @@
 ----
 
 
+.. _enable_breakpoint:
+
+:enable-breakpoint *point*
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+  Enable or create a breakpoint for the given [<format>:]<file>:<line> tuples or the current line
+
+  **Parameters**
+    * **point** --- The file and line number of the breakpoint
+
+
+----
+
+
 .. _enable_filter:
 
 :enable-filter *pattern*

src/internals/sql-ref.rst

@@ -3501,14 +3501,15 @@ radians(*degrees*)
 
 .. _raise_error:
 
-raise_error(*msg*, *\[reason\]*)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+raise_error(*msg*, *\[reason\]*, *\[help\]*)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
   Raises an error with the given message when executed
 
   **Parameters**
     * **msg\*** --- The error message
     * **reason** --- The reason the error occurred
+    * **help** --- A possible resolution to the error
 
   **Examples**
     To raise an error if a variable is not set:

src/lnav.cc

@@ -1578,7 +1578,10 @@ VALUES ('org.lnav.mouse-support', -1, DATETIME('now', '+1 minute'),
             }
         }
     };
-    auto click_handler = [](textview_curses& tc, const attr_line_t& al, int x) {
+    auto click_handler = [](textview_curses& tc,
+                            const attr_line_t& al,
+                            int x,
+                            const mouse_event& me) {
         if (tc.tc_selected_text) {
             return;
         }

src/scripts/lnav-moveto-breakpoint.lnav

@@ -5,17 +5,22 @@
 
 ;SELECT
     CASE
-      WHEN count(*) = 0 THEN raise_error('Cannot move to breakpoint', 'No breakpoints have been set yet')
+      WHEN name != 'log' THEN
+        raise_error('Cannot move to breakpoint',
+                    'Breakpoints are only supported in the LOG view')
       ELSE 1
     END
-  FROM lnav_log_breakpoints
+  FROM lnav_top_view
   UNION ALL
- SELECT
+  SELECT
     CASE
-      WHEN name != 'log' THEN raise_error('Cannot move to breakpoint', 'Breakpoints are only supported in the LOG view')
+      WHEN count(*) = 0 THEN
+        raise_error('Cannot move to breakpoint',
+                    'No breakpoints have been set yet',
+                    'Use CTRL-B or the :breakpoint command to set a breakpoint')
       ELSE 1
     END
-  FROM lnav_top_view;
+  FROM lnav_log_breakpoints
 
 ;SELECT
     CASE $1

src/state-extension-functions.cc

@@ -125,13 +125,18 @@ sql_lnav_version()
 }
 
 static int64_t
-sql_error(const char* str, std::optional<string_fragment> reason)
+sql_error(const char* str,
+          std::optional<string_fragment> reason,
+          std::optional<string_fragment> help)
 {
     auto um = lnav::console::user_message::error(str);
 
     if (reason) {
         um.with_reason(reason->to_string());
     }
+    if (help) {
+        um.with_help(help->to_string());
+    }
     throw um;
 }
 
@@ -202,6 +207,9 @@ state_extension_functions(struct FuncDef** basic_funcs,
                 .with_parameter(
                     help_text("reason", "The reason the error occurred")
                         .optional())
+                .with_parameter(
+                    help_text("help", "A possible resolution to the error")
+                        .optional())
                 .with_example({
                     "To raise an error if a variable is not set",
                     "SELECT ifnull($val, raise_error('please set $val', "