jobs.h

   1 /* jobs.h -- structures and definitions used by the jobs.c file. */
   2
   3 /* Copyright (C) 1993-2022  Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #if !defined (_JOBS_H_)
  22 #  define _JOBS_H_
  23
  24 #include "quit.h"
  25 #include "siglist.h"
  26
  27 #include "stdc.h"
  28
  29 #include "posixwait.h"
  30
  31 /* Defines controlling the fashion in which jobs are listed. */
  32 #define JLIST_STANDARD       0
  33 #define JLIST_LONG           1
  34 #define JLIST_PID_ONLY       2
  35 #define JLIST_CHANGED_ONLY   3
  36 #define JLIST_NONINTERACTIVE 4
  37
  38 /* I looked it up.  For pretty_print_job ().  The real answer is 24. */
  39 #define LONGEST_SIGNAL_DESC 24
  40
  41 /* Defines for the wait_for_* functions and for the wait builtin to use */
  42 #define JWAIT_PERROR            (1 << 0)
  43 #define JWAIT_FORCE             (1 << 1)
  44 #define JWAIT_NOWAIT            (1 << 2) /* don't waitpid(), just return status if already exited */
  45 #define JWAIT_WAITING           (1 << 3) /* wait for jobs marked J_WAITING only */
  46
  47 /* flags for wait_for */
  48 #define JWAIT_NOTERM            (1 << 8) /* wait_for doesn't give terminal away */
  49
  50 /* The max time to sleep while retrying fork() on EAGAIN failure */
  51 #define FORKSLEEP_MAX   16
  52
  53 /* We keep an array of jobs.  Each entry in the array is a linked list
  54    of processes that are piped together.  The first process encountered is
  55    the group leader. */
  56
  57 /* Values for the `running' field of a struct process. */
  58 #define PS_DONE         0
  59 #define PS_RUNNING      1
  60 #define PS_STOPPED      2
  61 #define PS_RECYCLED     4
  62
  63 /* Each child of the shell is remembered in a STRUCT PROCESS.  A circular
  64    chain of such structures is a pipeline. */
  65 typedef struct process {
  66   struct process *next; /* Next process in the pipeline.  A circular chain. */
  67   pid_t pid;            /* Process ID. */
  68   WAIT status;          /* The status of this command as returned by wait. */
  69   int running;          /* Non-zero if this process is running. */
  70   char *command;        /* The particular program that is running. */
  71 } PROCESS;
  72
  73 struct pipeline_saver {
  74   struct process *pipeline;
  75   struct pipeline_saver *next;
  76 };
  77
  78 /* PALIVE really means `not exited' */
  79 #define PSTOPPED(p)     (WIFSTOPPED((p)->status))
  80 #define PRUNNING(p)     ((p)->running == PS_RUNNING)
  81 #define PALIVE(p)       (PRUNNING(p) || PSTOPPED(p))
  82
  83 #define PEXITED(p)      ((p)->running == PS_DONE)
  84 #if defined (RECYCLES_PIDS)
  85 #  define PRECYCLED(p)  ((p)->running == PS_RECYCLED)
  86 #else
  87 #  define PRECYCLED(p)  (0)
  88 #endif
  89 #define PDEADPROC(p)    (PEXITED(p) || PRECYCLED(p))
  90
  91 #define get_job_by_jid(ind)     (jobs[(ind)])
  92
  93 /* A description of a pipeline's state. */
  94 typedef enum { JNONE = -1, JRUNNING = 1, JSTOPPED = 2, JDEAD = 4, JMIXED = 8 } JOB_STATE;
  95 #define JOBSTATE(job)   (jobs[(job)]->state)
  96 #define J_JOBSTATE(j)   ((j)->state)
  97
  98 #define STOPPED(j)      (jobs[(j)]->state == JSTOPPED)
  99 #define RUNNING(j)      (jobs[(j)]->state == JRUNNING)
 100 #define DEADJOB(j)      (jobs[(j)]->state == JDEAD)
 101
 102 #define INVALID_JOB(j)  ((j) < 0 || (j) >= js.j_jobslots || get_job_by_jid(j) == 0)
 103
 104 /* Values for the FLAGS field in the JOB struct below. */
 105 #define J_FOREGROUND 0x01 /* Non-zero if this is running in the foreground.  */
 106 #define J_NOTIFIED   0x02 /* Non-zero if already notified about job state.   */
 107 #define J_JOBCONTROL 0x04 /* Non-zero if this job started under job control. */
 108 #define J_NOHUP      0x08 /* Don't send SIGHUP to job if shell gets SIGHUP. */
 109 #define J_STATSAVED  0x10 /* A process in this job had status saved via $! */
 110 #define J_ASYNC      0x20 /* Job was started asynchronously */
 111 #define J_PIPEFAIL   0x40 /* pipefail set when job was started */
 112 #define J_WAITING    0x80 /* one of a list of jobs for which we are waiting */
 113
 114 #define IS_FOREGROUND(j)        ((jobs[j]->flags & J_FOREGROUND) != 0)
 115 #define IS_NOTIFIED(j)          ((jobs[j]->flags & J_NOTIFIED) != 0)
 116 #define IS_JOBCONTROL(j)        ((jobs[j]->flags & J_JOBCONTROL) != 0)
 117 #define IS_ASYNC(j)             ((jobs[j]->flags & J_ASYNC) != 0)
 118 #define IS_WAITING(j)           ((jobs[j]->flags & J_WAITING) != 0)
 119
 120 typedef struct job {
 121   char *wd;        /* The working directory at time of invocation. */
 122   PROCESS *pipe;   /* The pipeline of processes that make up this job. */
 123   pid_t pgrp;      /* The process ID of the process group (necessary). */
 124   JOB_STATE state; /* The state that this job is in. */
 125   int flags;       /* Flags word: J_NOTIFIED, J_FOREGROUND, or J_JOBCONTROL. */
 126 #if defined (JOB_CONTROL)
 127   COMMAND *deferred;    /* Commands that will execute when this job is done. */
 128   sh_vptrfunc_t *j_cleanup; /* Cleanup function to call when job marked JDEAD */
 129   PTR_T cleanarg;       /* Argument passed to (*j_cleanup)() */
 130 #endif /* JOB_CONTROL */
 131 } JOB;
 132
 133 struct jobstats {
 134   /* limits */
 135   long c_childmax;
 136   /* child process statistics */
 137   int c_living;         /* running or stopped child processes */
 138   int c_reaped;         /* exited child processes still in jobs list */
 139   int c_injobs;         /* total number of child processes in jobs list */
 140   /* child process totals */
 141   int c_totforked;      /* total number of children this shell has forked */
 142   int c_totreaped;      /* total number of children this shell has reaped */
 143   /* job counters and indices */
 144   int j_jobslots;       /* total size of jobs array */
 145   int j_lastj;          /* last (newest) job allocated */
 146   int j_firstj;         /* first (oldest) job allocated */
 147   int j_njobs;          /* number of non-NULL jobs in jobs array */
 148   int j_ndead;          /* number of JDEAD jobs in jobs array */
 149   /* */
 150   int j_current;        /* current job */
 151   int j_previous;       /* previous job */
 152   /* */
 153   JOB *j_lastmade;      /* last job allocated by stop_pipeline */
 154   JOB *j_lastasync;     /* last async job allocated by stop_pipeline */
 155 };
 156
 157 /* Revised to accommodate new hash table bgpids implementation. */
 158 typedef pid_t ps_index_t;
 159
 160 struct pidstat {
 161   ps_index_t bucket_next;
 162   ps_index_t bucket_prev;
 163
 164   pid_t pid;
 165   bits16_t status;              /* only 8 bits really needed */
 166 };
 167
 168 struct bgpids {
 169   struct pidstat *storage;      /* storage arena */
 170
 171   ps_index_t head;
 172   ps_index_t nalloc;
 173
 174   int npid;
 175 };
 176
 177 #define NO_PIDSTAT (ps_index_t)-1
 178
 179 /* standalone process status struct, without bgpids indexes */
 180 struct procstat {
 181   pid_t pid;
 182   bits16_t status;
 183 };
 184
 185 /* A standalone singly-linked list of PROCESS *, used in various places
 186    including keeping track of process substitutions. */
 187 struct procchain {
 188   PROCESS *head;
 189   PROCESS *end;
 190   int nproc;
 191 };
 192
 193 #define NO_JOB  -1      /* An impossible job array index. */
 194 #define DUP_JOB -2      /* A possible return value for get_job_spec (). */
 195 #define BAD_JOBSPEC -3  /* Bad syntax for job spec. */
 196
 197 /* A value which cannot be a process ID. */
 198 #define NO_PID (pid_t)-1
 199
 200 #define ANY_PID (pid_t)-1
 201
 202 /* flags for make_child () */
 203 #define FORK_SYNC       0               /* normal synchronous process */
 204 #define FORK_ASYNC      1               /* background process */
 205 #define FORK_NOJOB      2               /* don't put process in separate pgrp */
 206 #define FORK_NOTERM     4               /* don't give terminal to any pgrp */
 207
 208 /* System calls. */
 209 #if !defined (HAVE_UNISTD_H)
 210 extern pid_t fork (), getpid (), getpgrp ();
 211 #endif /* !HAVE_UNISTD_H */
 212
 213 /* Stuff from the jobs.c file. */
 214 extern struct jobstats js;
 215
 216 extern pid_t original_pgrp, shell_pgrp, pipeline_pgrp;
 217 extern volatile pid_t last_made_pid, last_asynchronous_pid;
 218 extern int asynchronous_notification;
 219
 220 extern int already_making_children;
 221 extern int running_in_background;
 222
 223 extern PROCESS *last_procsub_child;
 224
 225 extern JOB **jobs;
 226
 227 extern void making_children PARAMS((void));
 228 extern void stop_making_children PARAMS((void));
 229 extern void cleanup_the_pipeline PARAMS((void));
 230 extern void discard_last_procsub_child PARAMS((void));
 231 extern void save_pipeline PARAMS((int));
 232 extern PROCESS *restore_pipeline PARAMS((int));
 233 extern void start_pipeline PARAMS((void));
 234 extern int stop_pipeline PARAMS((int, COMMAND *));
 235 extern int discard_pipeline PARAMS((PROCESS *));
 236 extern void append_process PARAMS((char *, pid_t, int, int));
 237
 238 extern void save_proc_status PARAMS((pid_t, int));
 239
 240 extern PROCESS *procsub_add PARAMS((PROCESS *));
 241 extern PROCESS *procsub_search PARAMS((pid_t));
 242 extern PROCESS *procsub_delete PARAMS((pid_t));
 243 extern int procsub_waitpid PARAMS((pid_t));
 244 extern void procsub_waitall PARAMS((void));
 245 extern void procsub_clear PARAMS((void));
 246 extern void procsub_prune PARAMS((void));
 247
 248 extern void delete_job PARAMS((int, int));
 249 extern void nohup_job PARAMS((int));
 250 extern void delete_all_jobs PARAMS((int));
 251 extern void nohup_all_jobs PARAMS((int));
 252
 253 extern int count_all_jobs PARAMS((void));
 254
 255 extern void terminate_current_pipeline PARAMS((void));
 256 extern void terminate_stopped_jobs PARAMS((void));
 257 extern void hangup_all_jobs PARAMS((void));
 258 extern void kill_current_pipeline PARAMS((void));
 259
 260 #if defined (__STDC__) && defined (pid_t)
 261 extern int get_job_by_pid PARAMS((int, int, PROCESS **));
 262 extern void describe_pid PARAMS((int));
 263 #else
 264 extern int get_job_by_pid PARAMS((pid_t, int, PROCESS **));
 265 extern void describe_pid PARAMS((pid_t));
 266 #endif
 267
 268 extern void list_one_job PARAMS((JOB *, int, int, int));
 269 extern void list_all_jobs PARAMS((int));
 270 extern void list_stopped_jobs PARAMS((int));
 271 extern void list_running_jobs PARAMS((int));
 272
 273 extern pid_t make_child PARAMS((char *, int));
 274
 275 extern int get_tty_state PARAMS((void));
 276 extern int set_tty_state PARAMS((void));
 277
 278 extern int job_exit_status PARAMS((int));
 279 extern int job_exit_signal PARAMS((int));
 280
 281 extern int wait_for_single_pid PARAMS((pid_t, int));
 282 extern int wait_for_background_pids PARAMS((struct procstat *));
 283 extern int wait_for PARAMS((pid_t, int));
 284 extern int wait_for_job PARAMS((int, int, struct procstat *));
 285 extern int wait_for_any_job PARAMS((int, struct procstat *));
 286
 287 extern void wait_sigint_cleanup PARAMS((void));
 288
 289 extern void notify_and_cleanup PARAMS((void));
 290 extern void reap_dead_jobs PARAMS((void));
 291 extern int start_job PARAMS((int, int));
 292 extern int kill_pid PARAMS((pid_t, int, int));
 293 extern int initialize_job_control PARAMS((int));
 294 extern void initialize_job_signals PARAMS((void));
 295 extern int give_terminal_to PARAMS((pid_t, int));
 296
 297 extern void run_sigchld_trap PARAMS((int));
 298
 299 extern int freeze_jobs_list PARAMS((void));
 300 extern void unfreeze_jobs_list PARAMS((void));
 301 extern void set_jobs_list_frozen PARAMS((int));
 302 extern int set_job_control PARAMS((int));
 303 extern void without_job_control PARAMS((void));
 304 extern void end_job_control PARAMS((void));
 305 extern void restart_job_control PARAMS((void));
 306 extern void set_sigchld_handler PARAMS((void));
 307 extern void ignore_tty_job_signals PARAMS((void));
 308 extern void default_tty_job_signals PARAMS((void));
 309 extern void get_original_tty_job_signals PARAMS((void));
 310
 311 extern void init_job_stats PARAMS((void));
 312
 313 extern void close_pgrp_pipe PARAMS((void));
 314 extern void save_pgrp_pipe PARAMS((int *, int));
 315 extern void restore_pgrp_pipe PARAMS((int *));
 316
 317 extern void set_maxchild PARAMS((int));
 318
 319 #ifdef DEBUG
 320 extern void debug_print_pgrps (void);
 321 #endif
 322
 323 extern int job_control;         /* set to 0 in nojobs.c */
 324
 325 #endif /* _JOBS_H_ */