diff options
| -rw-r--r-- | src/vmon.c | 77 |
1 files changed, 74 insertions, 3 deletions
@@ -1,7 +1,7 @@ /* * \/\/\ * - * Copyright (C) 2012-2025 Vito Caputo - <vcaputo@pengaru.com> + * Copyright (C) 2012-2026 Vito Caputo - <vcaputo@pengaru.com> * * This program is free software: you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published @@ -55,6 +55,7 @@ typedef struct vmon_t { time_t start_time; int snapshots_interval; int snapshot; + char *strobe_file; int marker_distance; int now_names; int headless; @@ -74,7 +75,7 @@ typedef struct vmon_t { #define WIDTH_MIN 200 #define HEIGHT_MIN 28 -static volatile int got_sigchld, got_sigusr1, got_sigint, got_sigquit, got_sigterm; +static volatile int got_sigchld, got_sigusr1, got_sigusr2, got_sigint, got_sigquit, got_sigterm; /* return if arg == flag or altflag if provided */ static int is_flag(const char *arg, const char *flag, const char *altflag) @@ -204,6 +205,7 @@ static void print_help(void) " -p --pid PID of the top-level process to monitor (1 if unspecified)\n" " -i --snapshots Save a PNG snapshot every N seconds (SIG{TERM,USR1} also snapshots)\n" " -s --snapshot Save a PNG snapshot upon receiving SIG{CHLD,TERM,USR1}\n" + " -S --strobe-file Save a PNG snapshot to this file path upon receiving SIGUSR2\n" " -w --wip-name Name to use for work-in-progress snapshot filename\n" " -v --version Print version\n" " -D --dump-procs Dump libvmon internal processes table (debugging aid)\n" @@ -227,7 +229,7 @@ static void print_copyright(void) { puts( "\n" - "Copyright (C) 2012-2025 Vito Caputo <vcaputo@pengaru.com>\n" + "Copyright (C) 2012-2026 Vito Caputo <vcaputo@pengaru.com>\n" "\n" "This program comes with ABSOLUTELY NO WARRANTY. This is free software, and\n" "you are welcome to redistribute it under certain conditions. For details\n" @@ -249,6 +251,12 @@ static void handle_sigusr1(int signum) got_sigusr1 = 1; } +/* trigger a strobe (in-place snapshot to a fixed name) */ +static void handle_sigusr2(int signum) +{ + got_sigusr2 = 1; +} + /* trigger a snapshot and exit immediately after it's been written */ static void handle_sigterm(int signum) @@ -462,6 +470,11 @@ static int vmon_handle_argv(vmon_t *vmon, int argc, const char * const *argv) } else if (is_flag(*argv, "-s", "--snapshot")) { vmon->snapshot = 1; last = argv; + } else if (is_flag(*argv, "-S", "--strobe-file")) { + if (!parse_flag_str(argv, end, argv + 1, 1, &vmon->strobe_file)) + return 0; + + last = ++argv; } else if (is_flag(*argv, "-w", "--wip-name")) { if (!parse_flag_str(argv, end, argv + 1, 1, &vmon->wip_name)) return 0; @@ -665,6 +678,13 @@ static vmon_t * vmon_startup(int argc, const char * const *argv) goto _err_vcr; } + if (vmon->strobe_file) { + if (signal(SIGUSR2, handle_sigusr2) == SIG_ERR) { + VWM_PERROR("unable to set SIGUSR2 handler"); + goto _err_vcr; + } + } + if (signal(SIGALRM, handle_sigusr1) == SIG_ERR) { VWM_PERROR("unable to set SIGALRM handler"); goto _err_vcr; @@ -787,6 +807,48 @@ static void vmon_resize(vmon_t *vmon, int width, int height) } +/* this is like vmon_snapshot() except in-place at a fixed name; truncates what's there, no atomicity */ +static int vmon_strobe(vmon_t *vmon) +{ +#ifdef USE_PNG + FILE *output; + + assert(vmon); + assert(vmon->strobe_file); + + output = fopen(vmon->strobe_file, "w+"); + if (!output) + return -errno; + + { + vcr_dest_t *png_dest; + + png_dest = vcr_dest_png_new(vmon->vcr_backend, output); + if (!png_dest) { + (void) unlink(vmon->strobe_file); + (void) fclose(output); + return -ENOMEM; + } + + if (vmon->headless) + vwm_chart_compose(vmon->charts, vmon->chart); + + /* FIXME: render/libpng errors need to propagate and be handled */ + vwm_chart_render(vmon->charts, vmon->chart, VCR_PRESENT_OP_SRC, png_dest, -1, -1, -1, -1); + png_dest = vcr_dest_free(png_dest); + } + + fflush(output); + fsync(fileno(output)); + fclose(output); + + return 0; +#else + return -ENOTSUP; +#endif +} + + static int vmon_snapshot(vmon_t *vmon) { #ifdef USE_PNG @@ -991,6 +1053,15 @@ int main(int argc, const char * const *argv) } } + if (got_sigusr2) { + int r; + + if ((r = vmon_strobe(vmon)) < 0) + VWM_ERROR("error saving strobe file: %s", strerror(-r)); + + got_sigusr2 = 0; + } + if (got_sigusr1 || (vmon->snapshots_interval && !vmon->n_snapshots)) { int r; |