Setup cli routing & other cleanup.

include/cli.h

@@ -0,0 +1,9 @@
+#pragma once
+
+#include "pch.h"
+
+namespace crib::cli {
+extern bool use_colors;
+void help();
+int run(int argc, char *argv[]);
+} // namespace crib::cli

include/cli/cli.h

@@ -1,3 +0,0 @@
-#pragma once
-
-#include "pch.h"

include/commands/ed/ed.h

@@ -2,3 +2,9 @@
 
 #include "internal/vase/vase.h"
 #include "pch.h"
+
+namespace crib::commands::ed {
+std::string summary();
+void help();
+void run(int argc, char *argv[]);
+} // namespace crib::commands::ed

include/internal/vase/vase.h

@@ -18,28 +18,28 @@ struct Range {
   Point end;
 };
 
-struct RegexGroup {
-  uint64_t start{UINT32_MAX};
-  uint64_t end{UINT32_MAX};
-};
-
-struct RegexMatch {
-  uint64_t start;
-  uint64_t end;
-  RegexGroup groups[9]{};
-};
-
-struct ReplacePart {
-  enum struct PartType {
-    FullMatch,
-    CaptureGroup,
-    Constant
-  } type;
-
-  std::variant<uint8_t, Shard *> value;
-};
-
 struct Vase {
+  struct RegexGroup {
+    uint64_t start{0};
+    uint64_t end{0};
+  };
+
+  struct RegexMatch {
+    uint64_t start;
+    uint64_t end;
+    RegexGroup groups[9]{};
+  };
+
+  struct ReplacePart {
+    enum struct PartType {
+      FullMatch,
+      CaptureGroup,
+      Constant
+    } type;
+
+    std::variant<uint8_t, Shard *> value;
+  };
+
   OriginalBuffer *original;
   AppendBuffer *append;
   Shard *root;

src/cli/cli.cc

@@ -0,0 +1,83 @@
+#include "cli.h"
+#include "commands/ed/ed.h"
+
+namespace crib::cli {
+struct Command {
+  void (*run)(int, char **);
+  std::string (*summary)();
+  void (*help)();
+};
+
+struct cli_error : std::runtime_error {
+  int exit_code;
+  cli_error(std::string msg, int code)
+      : std::runtime_error(std::move(msg)), exit_code(code) {}
+};
+
+static const std::unordered_map<std::string, Command> commands = {
+  {"ed",
+   {crib::commands::ed::run,
+    crib::commands::ed::summary,
+    crib::commands::ed::help}},
+};
+
+bool use_color() {
+  if (std::getenv("NO_COLOR"))
+    return false;
+  if (std::getenv("CLICOLOR_FORCE"))
+    return true;
+  if (!isatty(STDERR_FILENO))
+    return false;
+  const char *term = std::getenv("TERM");
+  if (!term || std::string_view(term) == "dumb" || std::string_view(term) == "xterm")
+    return false;
+  if (const char *clicolor = std::getenv("CLICOLOR"))
+    return std::string_view(clicolor) != "0";
+  return true;
+}
+
+bool use_colors = use_color();
+
+void help() {
+  std::cout << "Usage: crib <command> [options]\n\n"
+            << "Where command is one of\n";
+  for (auto &[name, cmd] : commands)
+    std::cout << "  " << name << " - " << cmd.summary() << "\n";
+}
+
+int execute(const std::string &name, const Command &cmd, int argc, char **argv) {
+  try {
+    cmd.run(argc - 1, argv + 1);
+    return 0;
+  } catch (const cli_error &e) {
+    std::cerr << "Error running " << name << ": " << e.what() << '\n';
+    return e.exit_code;
+  } catch (const std::exception &e) {
+    std::cerr << "Error running " << name << ": " << e.what() << '\n';
+    return 1;
+  } catch (...) {
+    std::cerr << "Unknown error running " << name << '\n';
+    return 1;
+  }
+}
+
+int run(int argc, char *argv[]) {
+  std::string invoked_as = std::filesystem::path(argv[0]).filename();
+
+  if (auto it = commands.find(invoked_as); it != commands.end())
+    return execute(it->first, it->second, argc, argv);
+
+  if (argc > 1)
+    if (auto it = commands.find(argv[1]); it != commands.end())
+      return execute(it->first, it->second, argc, argv);
+
+  if (argc > 1 && std::string(argv[1]) == "--help") {
+    help();
+    return 0;
+  }
+
+  std::cerr << "Invalid command given.\n\n";
+  help();
+  return 2;
+}
+} // namespace crib::cli

src/commands/ed/ed.cc

@@ -0,0 +1,11 @@
+#include "commands/ed/ed.h"
+
+namespace crib::commands::ed {
+std::string summary() {
+  return "A POSIX-compliant line editor.";
+}
+void help() {}
+void run(int, char *[]) {
+  return;
+}
+} // namespace crib::commands::ed

src/internal/vase/regex/api.cc

@@ -1,7 +1,7 @@
 #include "internal/vase/vase.h"
 
 namespace crib::internal::vase {
-std::vector<ReplacePart> Vase::parse_replace(std::string_view s) {
+std::vector<Vase::ReplacePart> Vase::parse_replace(std::string_view s) {
   std::vector<ReplacePart> parts;
   std::string constant;
   auto flush_constant = [&]() {
@@ -100,7 +100,7 @@ void Vase::regex_search_replace(
         uint8_t idx = std::get<uint8_t>(part.value);
         if (idx <= 9) {
           const RegexGroup &group = match.groups[idx - 1];
-          if (group.start != UINT32_MAX) {
+          if (group.start > group.end) {
             uint64_t ls = group.start - match.start;
             uint64_t le = group.end - match.start;
             auto [a, b] = Shard::split(dropped, ls);

src/internal/vase/regex/core.cc

@@ -1,7 +1,7 @@
 #include "internal/vase/vase.h"
 
 namespace crib::internal::vase {
-std::vector<RegexMatch> Vase::_regex_search(
+std::vector<Vase::RegexMatch> Vase::_regex_search(
   std::string_view pattern, Range range, std::string_view options
 ) {
   bool global = false;

src/main.cc

@@ -1,5 +1,6 @@
-#include "cli/cli.h"
+#include "cli.h"
 #include "pch.h"
 
 int main(int argc, char *argv[]) {
+  return crib::cli::run(argc, argv);
 }