init commit

3sem/cnts/contest12/04.c

@@ -0,0 +1,89 @@
+#include <unistd.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <linux/limits.h>
+#include <time.h>
+
+int
+main(int argc, char **argv)
+{
+    if (argc < 2) {
+        return 1;
+    }
+
+    char script_template[] = "#!/usr/bin/env python3\n"
+                             "import os\n"
+                             "print(";
+    char script_end[] = ")\n"
+                        "os.remove(__file__)\n";
+
+    size_t script_size = strlen(script_template) + strlen(script_end) + 1;
+    for (int i = 1; i < argc; i++) {
+        script_size += strlen(argv[i]) + 1;
+    }
+
+    char *script_content;
+    if (!(script_content = malloc(script_size))) {
+        return 1;
+    }
+
+    strcpy(script_content, script_template);
+
+    for (int i = 1; i < argc; i++) {
+        strcat(script_content, argv[i]);
+
+        if (i < argc - 1) {
+            strcat(script_content, "*");
+        }
+    }
+
+    strcat(script_content, script_end);
+
+    char *tmpdir = getenv("XDG_RUNTIME_DIR");
+    if (!tmpdir) {
+        tmpdir = getenv("TMPDIR");
+
+        if (!tmpdir) {
+            tmpdir = "/tmp";
+        }
+    }
+
+    char script_path[PATH_MAX];
+    int r = snprintf(script_path, sizeof(script_path), "%s/%d", tmpdir, (int) (getpid() * time(NULL) % 1000000));
+    if (r < 0 || r > PATH_MAX) {
+        exit(1);
+    }
+
+    int fd = open(script_path, O_RDWR | O_CREAT | O_EXCL, 0600);
+    if (fd == -1) {
+        free(script_content);
+        return 1;
+    }
+
+    FILE *script_file = fdopen(fd, "w");
+    if (!script_file) {
+        close(fd);
+        unlink(script_path);
+        free(script_content);
+        return 1;
+    }
+
+    fprintf(script_file, "%s", script_content);
+    fclose(script_file);
+    free(script_content);
+
+    if (chmod(script_path, 0700) == -1) {
+        unlink(script_path);
+        return 1;
+    }
+
+    execl(script_path, script_path, (char *) NULL);
+    unlink(script_path);
+
+    return 1;
+}