X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fcommand-line.c;h=cb73a25c90c46500a60a0ab79a7fda7baffc6b9b;hb=5c09b672114fab2357c8ce71d608d486eb5ae1ae;hp=a2a43a1c3ce0426793cdbf21a59d35b96ae9c04f;hpb=675febfa2f31372e45e2a6a28ce19256b22106d7;p=sliver-openvswitch.git diff --git a/lib/command-line.c b/lib/command-line.c index a2a43a1c3..cb73a25c9 100644 --- a/lib/command-line.c +++ b/lib/command-line.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011, 2013, 2014 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -19,9 +19,12 @@ #include #include #include +#include "ovs-thread.h" #include "util.h" #include "vlog.h" +VLOG_DEFINE_THIS_MODULE(command_line); + /* Given the GNU-style long options in 'options', returns a string that may be * passed to getopt() with the corresponding short options. The caller is * responsible for freeing the string. */ @@ -30,7 +33,7 @@ long_options_to_short_options(const struct option options[]) { char short_options[UCHAR_MAX * 3 + 1]; char *p = short_options; - + for (; options->name; options++) { const struct option *o = options; if (o->flag == NULL && o->val > 0 && o->val <= UCHAR_MAX) { @@ -44,7 +47,7 @@ long_options_to_short_options(const struct option options[]) } } *p = '\0'; - + return xstrdup(short_options); } @@ -67,23 +70,153 @@ run_command(int argc, char *argv[], const struct command commands[]) if (!strcmp(p->name, argv[0])) { int n_arg = argc - 1; if (n_arg < p->min_args) { - ovs_fatal(0, "'%s' command requires at least %d arguments", - p->name, p->min_args); + VLOG_FATAL( "'%s' command requires at least %d arguments", + p->name, p->min_args); } else if (n_arg > p->max_args) { - ovs_fatal(0, "'%s' command takes at most %d arguments", - p->name, p->max_args); + VLOG_FATAL("'%s' command takes at most %d arguments", + p->name, p->max_args); } else { p->handler(argc, argv); if (ferror(stdout)) { - ovs_fatal(0, "write to stdout failed"); + VLOG_FATAL("write to stdout failed"); } if (ferror(stderr)) { - ovs_fatal(0, "write to stderr failed"); + VLOG_FATAL("write to stderr failed"); } return; } } } - ovs_fatal(0, "unknown command '%s'; use --help for help", argv[0]); + VLOG_FATAL("unknown command '%s'; use --help for help", argv[0]); +} + +/* Process title. */ + +#ifdef __linux__ +static struct ovs_mutex proctitle_mutex = OVS_MUTEX_INITIALIZER; + +/* Start of command-line arguments in memory. */ +static char *argv_start OVS_GUARDED_BY(proctitle_mutex); + +/* Number of bytes of command-line arguments. */ +static size_t argv_size OVS_GUARDED_BY(proctitle_mutex); + +/* Saved command-line arguments. */ +static char *saved_proctitle OVS_GUARDED_BY(proctitle_mutex); + +/* Prepares the process so that proctitle_set() can later succeed. + * + * This modifies the argv[] array so that it no longer points into the memory + * that it originally does. Later, proctitle_set() might overwrite that + * memory. That means that this function should be called before anything else + * that accesses the process's argv[] array. Ideally, it should be called + * before anything else, period, at the very beginning of program + * execution. */ +void +proctitle_init(int argc, char **argv) +{ + int i; + + assert_single_threaded(); + if (!argc || !argv[0]) { + /* This situation should never occur, but... */ + return; + } + + ovs_mutex_lock(&proctitle_mutex); + /* Specialized version of first loop iteration below. */ + argv_start = argv[0]; + argv_size = strlen(argv[0]) + 1; + argv[0] = xstrdup(argv[0]); + + for (i = 1; i < argc; i++) { + size_t size = strlen(argv[i]) + 1; + + /* Add (argv[i], strlen(argv[i])+1) to (argv_start, argv_size). */ + if (argv[i] + size == argv_start) { + /* Arguments grow downward in memory. */ + argv_start -= size; + argv_size += size; + } else if (argv[i] == argv_start + argv_size) { + /* Arguments grow upward in memory. */ + argv_size += size; + } else { + /* Arguments not contiguous. (Is this really Linux?) */ + } + + /* Copy out the old argument so we can reuse the space. */ + argv[i] = xstrdup(argv[i]); + } + ovs_mutex_unlock(&proctitle_mutex); +} + +/* Changes the name of the process, as shown by "ps", to the program name + * followed by 'format', which is formatted as if by printf(). */ +void +proctitle_set(const char *format, ...) +{ + va_list args; + int n; + + ovs_mutex_lock(&proctitle_mutex); + if (!argv_start || argv_size < 8) { + goto out; + } + + if (!saved_proctitle) { + saved_proctitle = xmemdup(argv_start, argv_size); + } + + va_start(args, format); + n = snprintf(argv_start, argv_size, "%s: ", program_name); + if (n < argv_size) { + n += vsnprintf(argv_start + n, argv_size - n, format, args); + } + if (n >= argv_size) { + /* The name is too long, so add an ellipsis at the end. */ + strcpy(&argv_start[argv_size - 4], "..."); + } else { + /* Fill the extra space with null bytes, so that trailing bytes don't + * show up in the command line. */ + memset(&argv_start[n], '\0', argv_size - n); + } + va_end(args); + +out: + ovs_mutex_unlock(&proctitle_mutex); +} + +/* Restores the process's original command line, as seen by "ps". */ +void +proctitle_restore(void) +{ + ovs_mutex_lock(&proctitle_mutex); + if (saved_proctitle) { + memcpy(argv_start, saved_proctitle, argv_size); + free(saved_proctitle); + saved_proctitle = NULL; + } + ovs_mutex_unlock(&proctitle_mutex); +} +#else /* !__linux__ */ +/* Stubs that don't do anything on non-Linux systems. */ + +void +proctitle_init(int argc OVS_UNUSED, char **argv OVS_UNUSED) +{ +} + +#if !(defined(__FreeBSD__) || defined(__NetBSD__)) +/* On these platforms we #define this to setproctitle. */ +void +proctitle_set(const char *format OVS_UNUSED, ...) +{ +} +#endif + +void +proctitle_restore(void) +{ } +#endif /* !__linux__ */