feat: makefile project generation

1 files changed, 339 insertions, 9 deletions

diff --git a/mkproj.c b/mkproj.c
index 903a16c..66d3728 100644
--- a/mkproj.c
+++ b/mkproj.c
@@ -8,9 +8,15 @@
  * Version: 0.1.0
  */
 
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <unistd.h>
 
 #define mkproj_program "mkproj"
 #define mkproj_version "0.1.0"
@@ -56,6 +62,8 @@ struct Config
     enum Language language;
     const char *standard;
     enum Build_System build;
+    const char *bin_dir;
+    const char *bin_int_dir;
     int use_git;
     int use_intermediate;
     int use_clangd_ignore;
@@ -140,7 +148,7 @@ static void print_usage(FILE *stream)
         "have to keep writing build files for small dumb projects.\n"
         "\n"
         "usage: %s [-l lang] [-s std] [-b system] [--no-git] [--intermediate]\n"
-        "              [--no-clangd] <name>\n"
+        "              [--bin dir] [--bin-int dir] [--no-clangd] <name>\n"
         "       %s [-v | -h]\n"
         "\n"
         "options:\n"
@@ -149,6 +157,8 @@ static void print_usage(FILE *stream)
         "  -b, --build SYSTEM  build system: make, cmake, meson, premake (default make)\n"
         "      --no-git        don't initialize a git repository\n"
         "      --intermediate  use a separate intermediate object directory\n"
+        "      --bin DIR       output directory (default bin)\n"
+        "      --bin-int DIR   object dir; implies --intermediate (default bin-int)\n"
         "      --no-clangd     don't ignore clangd files in .gitignore\n"
         "  -v, --version       print version and bail\n"
         "  -h, --help          print this and bail\n"
@@ -248,6 +258,31 @@ static int parse_args(int argc, char **argv, struct Config *config)
             continue;
         }
 
+        if (strcmp(arg, "--bin") == 0)
+        {
+            if (++i >= argc)
+            {
+                error("missing argument for", arg);
+                return 1;
+            }
+
+            config->bin_dir = argv[i];
+            continue;
+        }
+
+        if (strcmp(arg, "--bin-int") == 0)
+        {
+            if (++i >= argc)
+            {
+                error("missing argument for", arg);
+                return 1;
+            }
+
+            config->bin_int_dir = argv[i];
+            config->use_intermediate = 1;
+            continue;
+        }
+
         if (strcmp(arg, "-l") == 0 || strcmp(arg, "--lang") == 0)
         {
             if (++i >= argc)
@@ -337,6 +372,305 @@ static int parse_args(int argc, char **argv, struct Config *config)
     return 0;
 }
 
+/* run argv to completion. returns the exit code, 127 if it could not be
+ * executed, or -1 on a fork/wait failure. */
+static int run(char *const argv[], int quiet)
+{
+    pid_t pid = fork();
+
+    if (pid < 0)
+        return -1;
+
+    if (pid == 0)
+    {
+        if (quiet)
+        {
+            int devnull = open("/dev/null", O_WRONLY);
+
+            if (devnull >= 0)
+            {
+                (void) dup2(devnull, STDOUT_FILENO);
+                (void) dup2(devnull, STDERR_FILENO);
+                (void) close(devnull);
+            }
+        }
+
+        (void) execvp(argv[0], argv);
+        _exit(127);
+    }
+
+    int status = 0;
+
+    if (waitpid(pid, &status, 0) < 0)
+        return -1;
+
+    if (WIFEXITED(status))
+        return WEXITSTATUS(status);
+
+    return -1;
+}
+
+static int git_init(const char *root)
+{
+    char *const argv[] = { "git", "-C", (char *) root, "init", NULL };
+
+    return run(argv, 1);
+}
+
+static const char *main_source(const struct Config *config)
+{
+    if (config->language == language_objc)
+        return
+            "#import <Foundation/Foundation.h>\n"
+            "\n"
+            "int main(void)\n"
+            "{\n"
+            "    @autoreleasepool {\n"
+            "        (void) NSLog(@\"type shi\");\n"
+            "    }\n"
+            "}\n";
+
+    if (config->language == language_cpp)
+    {
+        const char *std = config->standard;
+
+        if (strcmp(std, "c++23") == 0 || strcmp(std, "c++26") == 0)
+            return
+                "#include <print>\n"
+                "\n"
+                "auto main() -> int\n"
+                "{\n"
+                "    std::println(\"type shi\");\n"
+                "}\n";
+
+        if (strcmp(std, "c++98") == 0 || strcmp(std, "c++03") == 0)
+            return
+                "#include <iostream>\n"
+                "\n"
+                "int main()\n"
+                "{\n"
+                "    std::cout << \"type shi\\n\";\n"
+                "}\n";
+
+        return
+            "#include <iostream>\n"
+            "\n"
+            "auto main() -> int\n"
+            "{\n"
+            "    std::cout << \"type shi\\n\";\n"
+            "}\n";
+    }
+
+    return
+        "#include <stdio.h>\n"
+        "\n"
+        "int main(void)\n"
+        "{\n"
+        "    (void) puts(\"type shi\");\n"
+        "}\n";
+}
+
+static void write_main(FILE *out, const struct Config *config)
+{
+    (void) fputs(main_source(config), out);
+}
+
+static void write_makefile(FILE *out, const struct Config *config)
+{
+    const struct Language_Info *lang = &languages[config->language];
+    const char *ext = lang->extension;
+    const char *obj_dir =
+        config->use_intermediate ? config->bin_int_dir : config->bin_dir;
+
+    char clean[2 * PATH_MAX + 16];
+
+    if (config->use_intermediate)
+        (void) snprintf(clean, sizeof clean, "rm -rf %s %s",
+                        config->bin_dir, config->bin_int_dir);
+    else
+        (void) snprintf(clean, sizeof clean, "rm -rf %s", config->bin_dir);
+
+    const char *flags[10];
+    size_t count = 0;
+
+    flags[count++] = "-Wall";
+    flags[count++] = "-Wextra";
+    flags[count++] = "-Wpedantic";
+    flags[count++] = "-Wconversion";
+    flags[count++] = "-Wsign-conversion";
+    flags[count++] = "-Wshadow";
+
+    if (config->language != language_cpp)
+    {
+        flags[count++] = "-Wstrict-prototypes";
+        flags[count++] = "-Wmissing-prototypes";
+    }
+
+    flags[count++] = "-g";
+    flags[count++] = "-fno-omit-frame-pointer";
+
+    (void) fprintf(out, "CC := %s\n\nSANITIZE ?= 1\n\nCFLAGS := ", lang->compiler);
+
+    for (size_t i = 0; i < count; i++)
+        (void) fprintf(out, "%s \\\n          ", flags[i]);
+
+    (void) fprintf(out, "-std=%s \\\n          -Isrc\n", config->standard);
+
+    (void) fprintf(
+        out,
+        "\n"
+        "ifeq ($(SANITIZE),1)\n"
+        "CFLAGS += -fsanitize=address,undefined\n"
+        "LDFLAGS += -fsanitize=address,undefined\n"
+        "endif\n"
+        "\n"
+        "TARGET := %s/%s\n"
+        "SRC := $(shell find src -name '*.%s')\n"
+        "OBJ := $(SRC:src/%%=%s/%%.o)\n"
+        "\n"
+        "all: $(TARGET)\n"
+        "\n"
+        "$(TARGET): $(OBJ)\n"
+        "\t@mkdir -p $(@D)\n"
+        "\t$(CC) $^ -o $@ $(LDFLAGS)\n"
+        "\n"
+        "%s/%%.%s.o: src/%%.%s\n"
+        "\t@mkdir -p $(@D)\n"
+        "\t$(CC) $(CFLAGS) -c $< -o $@\n"
+        "\n"
+        "check:\n"
+        "\tbear -- make clean all\n"
+        "\tcppcheck \\\n"
+        "\t\t--project=compile_commands.json \\\n"
+        "\t\t--enable=warning,style,performance,portability \\\n"
+        "\t\t--error-exitcode=1\n"
+        "\n"
+        "clean:\n"
+        "\t%s\n"
+        "\n"
+        ".PHONY: all check clean\n",
+        config->bin_dir, config->name, ext,
+        obj_dir, obj_dir, ext, ext, clean);
+}
+
+static void write_gitignore(FILE *out, const struct Config *config)
+{
+    (void) fprintf(out, "%s/\n", config->bin_dir);
+
+    if (config->use_intermediate)
+        (void) fprintf(out, "%s/\n", config->bin_int_dir);
+
+    if (config->use_clangd_ignore)
+        (void) fputs(
+            "\n"
+            ".clangd\n"
+            "compile_flags.txt\n"
+            "compile_commands.json\n",
+            out);
+}
+
+/* open path, hand the stream to writer, close. returns 0 on success. */
+static int emit(const char *path, const struct Config *config,
+                void (*writer)(FILE *, const struct Config *))
+{
+    FILE *file = fopen(path, "w");
+
+    if (file == NULL)
+    {
+        error("cannot create file", path);
+        return -1;
+    }
+
+    writer(file, config);
+
+    if (fclose(file) != 0)
+    {
+        error("cannot write file", path);
+        return -1;
+    }
+
+    return 0;
+}
+
+static int make_dir(const char *path)
+{
+    if (mkdir(path, 0755) == 0)
+        return 0;
+
+    if (errno == EEXIST)
+        error("already exists", path);
+    else
+        error("cannot create directory", path);
+
+    return -1;
+}
+
+static void print_next_steps(const struct Config *config)
+{
+    (void) printf("\ncreated %s (%s, %s, %s)\n\n",
+                  config->name,
+                  languages[config->language].name,
+                  config->standard,
+                  build_systems[config->build].name);
+
+    (void) printf("  cd %s\n", config->name);
+    (void) printf("  make\n");
+    (void) printf("  make check\n\n");
+}
+
+static int generate_project(const struct Config *config)
+{
+    char path[PATH_MAX];
+
+    if (config->build != build_make)
+    {
+        error("build system not yet implemented",
+              build_systems[config->build].key);
+        return -1;
+    }
+
+    if (make_dir(config->name) != 0)
+        return -1;
+
+    (void) snprintf(path, sizeof path, "%s/src", config->name);
+
+    if (make_dir(path) != 0)
+        return -1;
+
+    (void) snprintf(path, sizeof path, "%s/src/main.%s",
+                    config->name, languages[config->language].extension);
+
+    if (emit(path, config, write_main) != 0)
+        return -1;
+
+    (void) snprintf(path, sizeof path, "%s/Makefile", config->name);
+
+    if (emit(path, config, write_makefile) != 0)
+        return -1;
+
+    (void) snprintf(path, sizeof path, "%s/.gitignore", config->name);
+
+    if (emit(path, config, write_gitignore) != 0)
+        return -1;
+
+    if (config->use_git && git_init(config->name) != 0)
+        (void) fprintf(stderr, "%s: warning: git is not installed\n",
+                       mkproj_program);
+
+    print_next_steps(config);
+
+    {
+        char *const argv[] =
+            { "tree", "-a", "--dirsfirst", "-I", ".git",
+              (char *) config->name, NULL };
+
+        if (run(argv, 0) == 127)
+            (void) puts("  (tree is not installed)");
+    }
+
+    return 0;
+}
+
 int main(int argc, char **argv)
 {
     struct Config config =
@@ -345,6 +679,8 @@ int main(int argc, char **argv)
         .language = language_c,
         .standard = NULL,
         .build = build_make,
+        .bin_dir = "bin",
+        .bin_int_dir = "bin-int",
         .use_git = 1,
         .use_intermediate = 0,
         .use_clangd_ignore = 1,
@@ -361,14 +697,8 @@ int main(int argc, char **argv)
         return EXIT_FAILURE;
     }
 
-    /* TODO: generation. for now, echo the resolved config. */
-    (void) printf("name:     %s\n", config.name);
-    (void) printf("language: %s\n", languages[config.language].name);
-    (void) printf("standard: %s\n", config.standard);
-    (void) printf("build:    %s\n", build_systems[config.build].name);
-    (void) printf("git:      %s\n", config.use_git ? "yes" : "no");
-    (void) printf("interm.:  %s\n", config.use_intermediate ? "yes" : "no");
-    (void) printf("clangd:   %s\n", config.use_clangd_ignore ? "yes" : "no");
+    if (generate_project(&config) != 0)
+        return EXIT_FAILURE;
 
     return EXIT_SUCCESS;
 }