init commit

3sem/cnts/contest13/01.c

@@ -0,0 +1,74 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <wait.h>
+#include <time.h>
+#include <sys/types.h>
+
+enum
+{
+    YEAR_OFFSET = 1900
+};
+
+int
+main(void)
+{
+
+    int fd[2];
+    pipe(fd);
+    time_t delta;
+    struct tm *dt;
+
+    pid_t pid = fork();
+    if (pid == 0) {
+        pid = fork();
+
+        if (pid == 0) {
+            pid = fork();
+
+            if (pid == 0) {
+                close(fd[0]);
+
+                delta = time(NULL);
+                if (write(fd[1], &delta, sizeof(delta)) == -1 || write(fd[1], &delta, sizeof(delta)) == -1 ||
+                    write(fd[1], &delta, sizeof(delta)) == -1) {
+                    _exit(1);
+                }
+            } else if (pid == -1) {
+                _exit(1);
+            }
+            close(fd[1]);
+            wait(NULL);
+            if (read(fd[0], &delta, sizeof(delta)) == -1) {
+                _exit(1);
+            }
+            dt = localtime(&delta);
+            printf("D:%02d\n", dt->tm_mday);
+            fflush(stdout);
+            _exit(0);
+        } else if (pid == -1) {
+            _exit(1);
+        }
+
+        close(fd[1]);
+        wait(NULL);
+        if (read(fd[0], &delta, sizeof(delta)) == -1) {
+            _exit(1);
+        }
+        dt = localtime(&delta);
+        printf("M:%02d\n", dt->tm_mon + 1);
+        fflush(stdout);
+        _exit(0);
+    } else if (pid == -1) {
+        _exit(1);
+    }
+    close(fd[1]);
+    wait(NULL);
+    if (read(fd[0], &delta, sizeof(delta)) == -1) {
+        _exit(1);
+    }
+    dt = localtime(&delta);
+    printf("Y:%04d\n", dt->tm_year + YEAR_OFFSET);
+    fflush(stdout);
+
+    return 0;
+}

3sem/cnts/contest13/03.c

@@ -0,0 +1,92 @@
+#include <unistd.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+
+enum
+{
+    ACCESS_FILE = 0660
+};
+
+int
+main(int argc, char **argv)
+{
+    char *cmd1 = argv[1];
+    char *cmd2 = argv[2];
+    char *cmd3 = argv[3];
+    char *file1 = argv[4];
+    char *file2 = argv[5];
+
+    int fd1 = open(file1, O_RDONLY);
+    int fd2 = open(file2, O_WRONLY | O_APPEND | O_CREAT, ACCESS_FILE);
+    if (fd1 == -1 || fd2 == -1) {
+        exit(1);
+    }
+
+    int fd[2];
+    if (pipe(fd) == -1) {
+        return 1;
+    }
+
+    pid_t pid = fork();
+    if (pid == 0) {
+        close(fd[0]);
+        if (dup2(fd[1], 1) == -1) {
+            _exit(1);
+        }
+
+        pid = fork();
+        if (pid == 0) {
+
+            if (dup2(fd1, 0) == -1) {
+                _exit(1);
+            }
+
+            execlp(cmd1, cmd1, NULL);
+            _exit(1);
+        } else if (pid == -1) {
+            exit(1);
+        }
+
+        int status;
+        wait(&status);
+
+        if (WIFEXITED(status) && !WEXITSTATUS(status)) {
+            pid = fork();
+            if (pid == 0) {
+                execlp(cmd2, cmd2, NULL);
+                _exit(1);
+            } else if (pid == -1) {
+                exit(1);
+            }
+
+            wait(NULL);
+        }
+
+        _exit(0);
+    } else if (pid == -1) {
+        exit(1);
+    }
+
+    close(fd[1]);
+    pid = fork();
+    if (pid == 0) {
+
+        if (dup2(fd2, 1) == -1 || dup2(fd[0], 0)) {
+            _exit(1);
+        }
+
+        execlp(cmd3, cmd3, NULL);
+        _exit(1);
+    } else if (pid == -1) {
+        exit(1);
+    }
+
+    close(fd[0]);
+
+    while (wait(NULL) != -1)
+        ;
+    return 0;
+}

3sem/cnts/contest13/04.c

@@ -0,0 +1,71 @@
+#include <unistd.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+
+void
+ex(void)
+{
+    // разослать SIGKILL
+    // а некому.
+
+    exit(1);
+}
+
+void
+swap(int *a, int *b)
+{
+    int tmp = *a;
+    *a = *b;
+    *b = tmp;
+
+    return;
+}
+
+int
+main(int argc, char **argv)
+{
+    int fd1[2];
+    int fd2[2];
+    if (close(2) == -1 || pipe(fd1) == -1 || pipe(fd2)) {
+        ex();
+    }
+
+    for (int i = 1; i < argc; ++i) {
+        pid_t pid = fork();
+        if (pid == 0) {
+
+            if (i != 1 && i != argc - 1) {
+                if (dup2(fd2[1], 1) == -1 || dup2(fd1[0], 0) == -1) {
+                    ex();
+                }
+            } else if (i == 1) {
+                if (dup2(fd2[1], 1) == -1) {
+                    ex();
+                }
+            } else {
+                if (dup2(fd1[0], 0) == -1) {
+                    ex();
+                }
+            }
+
+            close(fd1[0]);
+            close(fd1[1]);
+            close(fd2[0]);
+            close(fd2[1]);
+
+            execlp(argv[i], argv[i], NULL);
+            _exit(1);
+        } else if (pid == -1) {
+            ex();
+        }
+
+        swap(&fd1[0], &fd2[0]);
+        swap(&fd1[1], &fd2[1]);
+        wait(NULL);
+    }
+
+    return 0;
+}

3sem/cnts/contest13/05.c

@@ -0,0 +1,73 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <wait.h>
+
+int
+main(int argc, char **argv)
+{
+    int n = (int) strtoll(argv[1], NULL, 10);
+
+    int fd1[2];
+    int fd2[2];
+    pipe(fd1);
+    pipe(fd2);
+
+    int tmp = 1;
+    write(fd2[1], &tmp, sizeof(tmp));
+
+    if (!fork()) {
+        int i = 0;
+        close(fd1[0]);
+        close(fd2[1]);
+
+        while (i < n) {
+            if (read(fd2[0], &i, sizeof(i)) == -1) {
+                return 0;
+            }
+            if (i >= n) {
+                write(fd1[1], &i, sizeof(i));
+                break;
+            }
+            printf("%d %d\n", 1, i);
+            fflush(stdout);
+            i++;
+            write(fd1[1], &i, sizeof(i));
+        }
+
+        return 0;
+    } else if (!fork()) {
+        int i = 0;
+        close(fd2[0]);
+        close(fd1[1]);
+
+        while (i < n) {
+            if (read(fd1[0], &i, sizeof(i)) == -1) {
+                return 0;
+            }
+            if (i >= n) {
+                write(fd1[1], &i, sizeof(i));
+                break;
+            }
+            printf("%d %d\n", 2, i);
+            fflush(stdout);
+            i++;
+            write(fd2[1], &i, sizeof(i));
+        }
+
+        return 0;
+    }
+
+    close(fd1[0]);
+    close(fd1[1]);
+    close(fd2[0]);
+    close(fd2[1]);
+
+    while (wait(NULL) != -1)
+        ;
+
+    printf("Done\n");
+
+    return 0;
+}