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40 lines
1.3 KiB
Plaintext
40 lines
1.3 KiB
Plaintext
This is how hush runs commands:
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/* callsite: process_command_subs */
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generate_stream_from_list(struct pipe *head) - handles `cmds`
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create UNIX pipe
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[v]fork
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child:
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redirect pipe output to stdout
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_exit(run_list(head)); /* leaks memory */
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parent:
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return UNIX pipe's output fd
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/* head is freed by the caller */
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/* callsite: parse_and_run_stream */
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run_and_free_list(struct pipe *)
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run_list(struct pipe *)
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free_pipe_list(struct pipe *)
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/* callsites: generate_stream_from_list, run_and_free_list, pseudo_exec, run_pipe */
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run_list(struct pipe *) - handles "cmd; cmd2 && cmd3", while/for/do loops
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run_pipe - for every pipe in list
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/* callsite: run_list */
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run_pipe - runs "cmd1 | cmd2 | cmd3 [&]"
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run_list - used if only one cmd and it is of the form "{cmds;}"
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forks for every cmd if more than one cmd or if & is there
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pseudo_exec - runs each "cmdN" (handles builtins etc)
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/* callsite: run_pipe */
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pseudo_exec - runs "cmd" (handles builtins etc)
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exec - execs external programs
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run_list - used if cmdN is "(cmds)" or "{cmds;}"
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/* problem: putenv's malloced strings into environ -
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** with vfork they will leak into parent process
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*/
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/* problem with ENABLE_FEATURE_SH_STANDALONE:
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** run_applet_no_and_exit(a, argv) uses exit - this can interfere
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** with vfork - switch to _exit there?
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*/
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