diff options
Diffstat (limited to 'source3/locking')
| -rw-r--r-- | source3/locking/shmem.c | 414 |
1 files changed, 242 insertions, 172 deletions
diff --git a/source3/locking/shmem.c b/source3/locking/shmem.c index b63db1f168..2a4e4de129 100644 --- a/source3/locking/shmem.c +++ b/source3/locking/shmem.c @@ -311,71 +311,113 @@ static BOOL smb_shm_create_hash_table( unsigned int size ) static BOOL smb_shm_register_process(char *processreg_file, pid_t pid, BOOL *other_processes) { - int smb_shm_processes_fd = -1; - int nb_read; - pid_t other_pid; - SMB_OFF_T seek_back = -((SMB_OFF_T)sizeof(other_pid)); - SMB_OFF_T free_slot = -1; - SMB_OFF_T erased_slot; - - smb_shm_processes_fd = open(processreg_file, - read_only?O_RDONLY:(O_RDWR|O_CREAT), - SHM_FILE_MODE); - - if ( smb_shm_processes_fd < 0 ) - { - DEBUG(0,("ERROR smb_shm_register_process : processreg_file open failed with code %s\n",strerror(errno))); - return False; - } - - *other_processes = False; - - while ((nb_read = read(smb_shm_processes_fd, &other_pid, sizeof(other_pid))) > 0) - { - if(other_pid) + int smb_shm_processes_fd = -1; + int nb_read; + pid_t other_pid; + SMB_OFF_T seek_back = -((SMB_OFF_T)sizeof(other_pid)); + SMB_OFF_T free_slot = -1; + SMB_OFF_T erased_slot; + + smb_shm_processes_fd = open(processreg_file, + read_only?O_RDONLY:(O_RDWR|O_CREAT), + SHM_FILE_MODE); + + if ( smb_shm_processes_fd < 0 ) + { + DEBUG(0, ("ERROR smb_shm_register_process : processreg_file \ +open failed with code %s\n",strerror(errno))); + return False; + } + + *other_processes = False; + + while ((nb_read = read(smb_shm_processes_fd, &other_pid, sizeof(other_pid))) > 0) + { + if(other_pid) + { + if(process_exists(other_pid)) + *other_processes = True; + else { - if(process_exists(other_pid)) - *other_processes = True; - else - { - /* erase old pid */ - DEBUG(5,("smb_shm_register_process : erasing stale record for pid %d (seek_back = %.0f)\n", - (int)other_pid, (double)seek_back)); - other_pid = (pid_t)0; - erased_slot = sys_lseek(smb_shm_processes_fd, seek_back, SEEK_CUR); - write(smb_shm_processes_fd, &other_pid, sizeof(other_pid)); - if(free_slot < 0) - free_slot = erased_slot; - } + /* erase old pid */ + DEBUG(5,("smb_shm_register_process : erasing stale record \ +for pid %d (seek_back = %.0f)\n", (int)other_pid, (double)seek_back)); + other_pid = (pid_t)0; + if((erased_slot = sys_lseek(smb_shm_processes_fd, + seek_back, SEEK_CUR)) == -1) + { + DEBUG(0, ("ERROR smb_shm_register_process : sys_lseek failed \ +with error %s\n", strerror(errno))); + close(smb_shm_processes_fd); + return False; + } + + if(write(smb_shm_processes_fd, &other_pid, sizeof(other_pid)) == -1) + { + DEBUG(0, ("ERROR smb_shm_register_process : write failed \ +with error %s\n", strerror(errno))); + close(smb_shm_processes_fd); + return False; + } + + if(free_slot < 0) + free_slot = erased_slot; } - else - if(free_slot < 0) - free_slot = sys_lseek(smb_shm_processes_fd, seek_back, SEEK_CUR); - } - if (nb_read < 0) - { - DEBUG(0,("ERROR smb_shm_register_process : processreg_file read failed with code %s\n",strerror(errno))); + } + else + { + if(free_slot < 0) + { + if((free_slot = sys_lseek(smb_shm_processes_fd, + seek_back, SEEK_CUR))==-1) + { + DEBUG(0, ("ERROR smb_shm_register_process : sys_lseek \ +failed with error %s\n", strerror(errno))); + close(smb_shm_processes_fd); + return False; + } + } /* end if free_slot */ + } /* end else */ + } /* end if other_pid */ + + if (nb_read < 0) + { + DEBUG(0,("ERROR smb_shm_register_process : processreg_file read \ +failed with code %s\n",strerror(errno))); + close(smb_shm_processes_fd); + return False; + } + + if(free_slot < 0) + { + if((free_slot = sys_lseek(smb_shm_processes_fd, 0, SEEK_END)) == -1) + { + DEBUG(0,("ERROR smb_shm_register_process : sys_lseek failed with code %s\n",strerror(errno))); close(smb_shm_processes_fd); return False; - } - - if(free_slot < 0) - free_slot = sys_lseek(smb_shm_processes_fd, 0, SEEK_END); + } + } - DEBUG(5,("smb_shm_register_process : writing record for pid %d at offset %.0f\n", + DEBUG(5,("smb_shm_register_process : writing record for pid %d at offset %.0f\n", (int)pid, (double)free_slot)); - sys_lseek(smb_shm_processes_fd, free_slot, SEEK_SET); - if(write(smb_shm_processes_fd, &pid, sizeof(pid)) < 0) - { - DEBUG(0,("ERROR smb_shm_register_process : processreg_file write failed with code %s\n",strerror(errno))); - close(smb_shm_processes_fd); - return False; - } + if(sys_lseek(smb_shm_processes_fd, free_slot, SEEK_SET) == -1) + { + DEBUG(0,("ERROR smb_shm_register_process : sys_lseek failed with code %s\n",strerror(errno))); + close(smb_shm_processes_fd); + return False; + } - close(smb_shm_processes_fd); + if(write(smb_shm_processes_fd, &pid, sizeof(pid)) == -1) + { + DEBUG(0,("ERROR smb_shm_register_process : processreg_file write failed with code %s\n",strerror(errno))); + close(smb_shm_processes_fd); + return False; + } - return True; + close(smb_shm_processes_fd); + + return True; } static BOOL smb_shm_unregister_process(char *processreg_file, pid_t pid) @@ -754,136 +796,164 @@ static struct shmem_ops shmops = { ******************************************************************/ struct shmem_ops *smb_shm_open(int ronly) { - pstring file_name; - SMB_OFF_T filesize; - BOOL created_new = False; - BOOL other_processes = True; - SMB_OFF_T size = (SMB_OFF_T)lp_shmem_size(); - - read_only = ronly; + pstring file_name; + SMB_OFF_T filesize; + BOOL created_new = False; + BOOL other_processes = True; + SMB_OFF_T size = (SMB_OFF_T)lp_shmem_size(); - pstrcpy(file_name,lp_lockdir()); - if (!directory_exist(file_name,NULL)) { - if (read_only) return NULL; - mkdir(file_name,0755); - } - trim_string(file_name,"","/"); - if (!*file_name) return(False); - pstrcat(file_name, "/SHARE_MEM_FILE"); - - DEBUG(5,("smb_shm_open : using shmem file %s to be of size %.0f\n",file_name,(double)size)); - - smb_shm_fd = open(file_name, read_only?O_RDONLY:(O_RDWR|O_CREAT), - SHM_FILE_MODE); + read_only = ronly; - if ( smb_shm_fd < 0 ) - { - DEBUG(0,("ERROR smb_shm_open : open failed with code %s\n",strerror(errno))); + pstrcpy(file_name,lp_lockdir()); + if (!directory_exist(file_name,NULL)) { + if (read_only) return NULL; - } - - if (!smb_shm_global_lock()) - { - DEBUG(0,("ERROR smb_shm_open : can't do smb_shm_global_lock\n")); - return NULL; - } - - if( (filesize = sys_lseek(smb_shm_fd, 0, SEEK_END)) < 0) - { - DEBUG(0,("ERROR smb_shm_open : lseek failed with code %s\n",strerror(errno))); - smb_shm_global_unlock(); - close(smb_shm_fd); - return NULL; - } - - /* return the file offset to 0 to save on later seeks */ - sys_lseek(smb_shm_fd,0,SEEK_SET); - - if (filesize == 0) - { - /* we just created a new one */ - created_new = True; - } - - /* to find out if some other process is already mapping the file, - we use a registration file containing the processids of the file mapping processes - */ - - /* construct processreg file name */ - pstrcpy(smb_shm_processreg_name, file_name); - pstrcat(smb_shm_processreg_name, ".processes"); - - if (!read_only && - !smb_shm_register_process(smb_shm_processreg_name, getpid(), &other_processes)) - { + mkdir(file_name,0755); + } + trim_string(file_name,"","/"); + if (!*file_name) + return(False); + pstrcat(file_name, "/SHARE_MEM_FILE"); + + DEBUG(5,("smb_shm_open : using shmem file %s to be of size %.0f\n", + file_name,(double)size)); + + smb_shm_fd = open(file_name, read_only?O_RDONLY:(O_RDWR|O_CREAT), + SHM_FILE_MODE); + + if ( smb_shm_fd < 0 ) + { + DEBUG(0,("ERROR smb_shm_open : open failed with code %s\n",strerror(errno))); + return NULL; + } + + if (!smb_shm_global_lock()) + { + DEBUG(0,("ERROR smb_shm_open : can't do smb_shm_global_lock\n")); + return NULL; + } + + if( (filesize = sys_lseek(smb_shm_fd, 0, SEEK_END)) == -1) + { + DEBUG(0,("ERROR smb_shm_open : sys_lseek failed with code %s\n", + strerror(errno))); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + /* + * Return the file offset to 0 to save on later seeks. + */ + if(sys_lseek(smb_shm_fd,0,SEEK_SET) == -1) + { + DEBUG(0,("ERROR smb_shm_open : sys_lseek failed with code %s\n", + strerror(errno))); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + if (filesize == 0) + { + /* + * We just created a new one. + */ + created_new = True; + } + + /* + * To find out if some other process is already mapping the file, + * we use a registration file containing the processids of the file + * mapping processes. + */ + + /* construct processreg file name */ + pstrcpy(smb_shm_processreg_name, file_name); + pstrcat(smb_shm_processreg_name, ".processes"); + + if (!read_only && !smb_shm_register_process(smb_shm_processreg_name, + getpid(), &other_processes)) + { + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } + + if (!read_only && (created_new || !other_processes)) + { + /* we just created a new one, or are the first opener, lets set it size */ + if( sys_ftruncate(smb_shm_fd, size) <0) + { + DEBUG(0,("ERROR smb_shm_open : ftruncate failed with code %s\n", + strerror(errno))); + smb_shm_unregister_process(smb_shm_processreg_name, getpid()); smb_shm_global_unlock(); close(smb_shm_fd); return NULL; - } - - if (!read_only && (created_new || !other_processes)) - { - /* we just created a new one, or are the first opener, lets set it size */ - if( sys_ftruncate(smb_shm_fd, size) <0) - { - DEBUG(0,("ERROR smb_shm_open : ftruncate failed with code %s\n",strerror(errno))); - smb_shm_unregister_process(smb_shm_processreg_name, getpid()); - smb_shm_global_unlock(); - close(smb_shm_fd); - return NULL; - } - - /* paranoia */ - sys_lseek(smb_shm_fd,0,SEEK_SET); - - filesize = size; - } - - if (size != filesize ) - { - /* the existing file has a different size and we are not the first opener. - Since another process is still using it, we will use the file size */ - DEBUG(0,("WARNING smb_shm_open : filesize (%.0f) != expected size (%.0f), using filesize\n", - (double)filesize, (double)size)); + } - size = filesize; - } - - smb_shm_header_p = (struct SmbShmHeader *)mmap(NULL, size, - read_only?PROT_READ: - (PROT_READ | PROT_WRITE), - MAP_FILE | MAP_SHARED, - smb_shm_fd, 0); - /* WARNING, smb_shm_header_p can be different for different processes mapping the same file ! */ - if (smb_shm_header_p == (struct SmbShmHeader *)(-1)) - { - DEBUG(0,("ERROR smb_shm_open : mmap failed with code %s\n",strerror(errno))); + /* paranoia */ + if(sys_lseek(smb_shm_fd,0,SEEK_SET) == -1) + { + DEBUG(0,("ERROR smb_shm_open : sys_lseek failed with code %s\n", + strerror(errno))); smb_shm_unregister_process(smb_shm_processreg_name, getpid()); smb_shm_global_unlock(); close(smb_shm_fd); return NULL; - } + } + + filesize = size; + } + + if (size != filesize ) + { + /* the existing file has a different size and we are not the first opener. + Since another process is still using it, we will use the file size */ + DEBUG(0,("WARNING smb_shm_open : filesize (%.0f) != expected \ +size (%.0f), using filesize\n", (double)filesize, (double)size)); + + size = filesize; + } + + smb_shm_header_p = (struct SmbShmHeader *)mmap(NULL, size, + read_only?PROT_READ: (PROT_READ | PROT_WRITE), + MAP_FILE | MAP_SHARED, smb_shm_fd, 0); + + /* + * WARNING, smb_shm_header_p can be different for different + * processes mapping the same file ! + */ + if (smb_shm_header_p == (struct SmbShmHeader *)(-1)) + { + DEBUG(0,("ERROR smb_shm_open : mmap failed with code %s\n",strerror(errno))); + smb_shm_unregister_process(smb_shm_processreg_name, getpid()); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } - if (!read_only && (created_new || !other_processes)) - { - smb_shm_initialize(size); - /* Create the hash buckets for the share file entries. */ - smb_shm_create_hash_table(SHMEM_HASH_SIZE); - } - else if (!smb_shm_validate_header(size) ) - { - /* existing file is corrupt, samba admin should remove it by hand */ - DEBUG(0,("ERROR smb_shm_open : corrupt shared mem file, remove it manually\n")); - munmap((caddr_t)smb_shm_header_p, size); - smb_shm_unregister_process(smb_shm_processreg_name, getpid()); - smb_shm_global_unlock(); - close(smb_shm_fd); - return NULL; - } + if (!read_only && (created_new || !other_processes)) + { + smb_shm_initialize(size); + /* Create the hash buckets for the share file entries. */ + smb_shm_create_hash_table(SHMEM_HASH_SIZE); + } + else if (!smb_shm_validate_header(size) ) + { + /* existing file is corrupt, samba admin should remove it by hand */ + DEBUG(0,("ERROR smb_shm_open : corrupt shared mem file, remove it manually\n")); + munmap((caddr_t)smb_shm_header_p, size); + smb_shm_unregister_process(smb_shm_processreg_name, getpid()); + smb_shm_global_unlock(); + close(smb_shm_fd); + return NULL; + } - smb_shm_global_unlock(); - return &shmops; + smb_shm_global_unlock(); + return &shmops; } |