X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fpager.c;h=001927ce93e093e26a210a9326826e16d9c57b02;hp=6799787e85b0cf7d339e23d553b328b6fbd9d3ab;hb=c73d180dc4bbd87c945a524b42b672af2ffe2609;hpb=f89a3b6f5bf695186e7b9e6cc63993b1272e7569 diff --git a/src/shared/pager.c b/src/shared/pager.c index 6799787e8..001927ce9 100644 --- a/src/shared/pager.c +++ b/src/shared/pager.c @@ -32,19 +32,22 @@ static pid_t pager_pid = 0; -_noreturn_ static void pager_fallback(void) { +noreturn static void pager_fallback(void) { ssize_t n; + do { n = splice(STDIN_FILENO, NULL, STDOUT_FILENO, NULL, 64*1024, 0); } while (n > 0); + if (n < 0) { log_error("Internal pager failed: %m"); _exit(EXIT_FAILURE); } + _exit(EXIT_SUCCESS); } -int pager_open(void) { +int pager_open(bool jump_to_end) { int fd[2]; const char *pager; pid_t parent_pid; @@ -57,7 +60,7 @@ int pager_open(void) { if (!*pager || streq(pager, "cat")) return 0; - if (isatty(STDOUT_FILENO) <= 0) + if (!on_tty()) return 0; /* Determine and cache number of columns before we spawn the @@ -75,17 +78,23 @@ int pager_open(void) { if (pager_pid < 0) { r = -errno; log_error("Failed to fork pager: %m"); - close_pipe(fd); + safe_close_pair(fd); return r; } /* In the child start the pager */ if (pager_pid == 0) { + const char* less_opts; dup2(fd[0], STDIN_FILENO); - close_pipe(fd); + safe_close_pair(fd); - setenv("LESS", "FRSX", 0); + less_opts = getenv("SYSTEMD_LESS"); + if (!less_opts) + less_opts = "FRSXMK"; + if (jump_to_end) + less_opts = strappenda(less_opts, " +G"); + setenv("LESS", less_opts, 1); /* Make sure the pager goes away when the parent dies */ if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0) @@ -122,7 +131,7 @@ int pager_open(void) { return -errno; } - close_pipe(fd); + safe_close_pair(fd); return 1; } @@ -134,10 +143,63 @@ void pager_close(void) { /* Inform pager that we are done */ fclose(stdout); kill(pager_pid, SIGCONT); - wait_for_terminate(pager_pid, NULL); + (void) wait_for_terminate(pager_pid, NULL); pager_pid = 0; } bool pager_have(void) { return pager_pid > 0; } + +int show_man_page(const char *desc, bool null_stdio) { + const char *args[4] = { "man", NULL, NULL, NULL }; + char *e = NULL; + pid_t pid; + size_t k; + int r; + siginfo_t status; + + k = strlen(desc); + + if (desc[k-1] == ')') + e = strrchr(desc, '('); + + if (e) { + char *page = NULL, *section = NULL; + + page = strndupa(desc, e - desc); + section = strndupa(e + 1, desc + k - e - 2); + + args[1] = section; + args[2] = page; + } else + args[1] = desc; + + pid = fork(); + if (pid < 0) { + log_error("Failed to fork: %m"); + return -errno; + } + + if (pid == 0) { + /* Child */ + if (null_stdio) { + r = make_null_stdio(); + if (r < 0) { + log_error("Failed to kill stdio: %s", strerror(-r)); + _exit(EXIT_FAILURE); + } + } + + execvp(args[0], (char**) args); + log_error("Failed to execute man: %m"); + _exit(EXIT_FAILURE); + } + + r = wait_for_terminate(pid, &status); + if (r < 0) + return r; + + log_debug("Exit code %i status %i", status.si_code, status.si_status); + return status.si_status; +}