diff options
Diffstat (limited to 'Year_2/OS/alpha-stats.c')
| -rw-r--r-- | Year_2/OS/alpha-stats.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/Year_2/OS/alpha-stats.c b/Year_2/OS/alpha-stats.c new file mode 100644 index 0000000..b9b0a07 --- /dev/null +++ b/Year_2/OS/alpha-stats.c @@ -0,0 +1,214 @@ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ipc.h> +#include <sys/mman.h> +#include <sys/sem.h> +#include <sys/shm.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +int +WAIT(int id_sem, int n) +{ + struct sembuf sops[1] = { { n, -1, 0 } }; + return semop(id_sem, sops, 1); +} + +int +SIGNAL(int id_sem, int n) +{ + struct sembuf sops[1] = { { n, 1, 0 } }; + return semop(id_sem, sops, 1); +} + +void +al(int sh_char, int sh_stats, int id_sem) +{ + char* ch; + long* stats; + int index; + + if ((ch = (char*)shmat(sh_char, NULL, 0)) == (char*)-1) { + perror("shmat"); + exit(1); + } + + if ((stats = (long*)shmat(sh_stats, NULL, 0)) == (long*)-1) { + perror("shmat"); + exit(1); + } + + while (1) { + WAIT(id_sem, 1); + if (strcmp(ch, "exit") == 0) { + break; + } + + if (*ch >= 'A' && *ch <= 'Z') + *ch = *ch + 32; + + index = *ch - 97; + stats[index]++; + + SIGNAL(id_sem, 0); + } +} + +void +mz(int sh_char, int sh_stats, int id_sem) +{ + char* ch; + long* stats; + int index; + + if ((ch = (char*)shmat(sh_char, NULL, 0)) == (char*)-1) { + perror("shmat"); + exit(1); + } + + if ((stats = (long*)shmat(sh_stats, NULL, 0)) == (long*)-1) { + perror("shmat"); + exit(1); + } + + while (1) { + WAIT(id_sem, 2); + if (strcmp(ch, "exit") == 0) { + break; + } + + if (*ch >= 'A' && *ch <= 'Z') + *ch = *ch + 32; + + index = *ch - 97; + stats[index]++; + + SIGNAL(id_sem, 0); + } +} + +int +main(int argc, char* argv[]) +{ + int fd; + struct stat sb; + char* addr; + int sh_char, sh_stats; /* segments CHAR and STATS */ + long* msg_stats; + char* ch; + pid_t p_al, p_mz; + int id_sem; + int i; + int skip_wait_p; + + if (argc < 2) { + fprintf(stderr, "Usage: %s <file.txt>", argv[0]); + exit(1); + } + + if ((fd = open(argv[1], O_RDONLY)) == -1) { + perror("open"); + exit(1); + } + + fstat(fd, &sb); + + if ((addr = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0)) == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + if ((sh_char = shmget(IPC_PRIVATE, 1, IPC_CREAT | IPC_EXCL | 0644)) == -1) { + perror("shmget"); + exit(1); + } + + if ((sh_stats = shmget(IPC_PRIVATE, sizeof(long) * 26, IPC_CREAT | IPC_EXCL | 0644)) == -1) { + perror("shmget"); + exit(1); + } + + /* Set to 0 every stats element */ + if ((msg_stats = (long*)shmat(sh_stats, NULL, 0)) == (long*)-1) { + perror("shmat"); + exit(1); + } + + for (i = 0; i < 26; ++i) + *(msg_stats + i) = 0; + + /* Create 3 semaphores */ + if ((id_sem = semget(IPC_PRIVATE, 3, IPC_CREAT | IPC_EXCL | 0644)) == -1) { + perror("semget"); + exit(1); + } + + semctl(id_sem, 0, SETVAL, 1); + semctl(id_sem, 1, SETVAL, 0); + semctl(id_sem, 2, SETVAL, 0); + + p_al = fork(); + if (p_al == -1) { + perror("fork"); + exit(1); + } + + if (p_al == 0) { + al(sh_char, sh_stats, id_sem); + exit(0); + } + + p_mz = fork(); + if (p_mz == -1) { + perror("fork"); + exit(1); + } + + if (p_mz == 0) { + mz(sh_char, sh_stats, id_sem); + exit(0); + } + + if ((ch = (char*)shmat(sh_char, NULL, 0)) == (char*)-1) { + perror("shmat"); + exit(1); + } + + skip_wait_p = 0; + for (i = 0; i < sb.st_size; ++i) { + if (!skip_wait_p) + WAIT(id_sem, 0); + + strcpy(ch, addr + i); + + skip_wait_p = 0; + if ((*ch >= 'a' && *ch <= 'l') || (*ch >= 'A' && *ch <= 'L')) { + SIGNAL(id_sem, 1); + } else if ((*ch >= 'm' && *ch <= 'z') || (*ch >= 'M' && *ch <= 'Z')) { + SIGNAL(id_sem, 2); + } else { + skip_wait_p = 1; + } + } + + strcpy(ch, "exit"); + SIGNAL(id_sem, 1); + SIGNAL(id_sem, 2); + + wait(NULL); + wait(NULL); + + for (i = 0; i < 26; ++i) + printf("%c = %ld\n", i + 97, msg_stats[i]); + + shmctl(sh_char, IPC_RMID, NULL); + shmctl(sh_stats, IPC_RMID, NULL); + semctl(id_sem, 3, IPC_RMID); + munmap(addr, sb.st_size); + + return 0; +} |