diff options
| -rw-r--r-- | lib/env.c | 115 | ||||
| -rw-r--r-- | lib/lib.c | 47 | ||||
| -rw-r--r-- | lib/lib.h | 7 | ||||
| -rwxr-xr-x | tests/env.test | 1 | ||||
| -rw-r--r-- | toys/posix/env.c | 19 |
5 files changed, 130 insertions, 59 deletions
diff --git a/lib/env.c b/lib/env.c new file mode 100644 index 00000000..94ea0a4e --- /dev/null +++ b/lib/env.c @@ -0,0 +1,115 @@ +// Can't trust libc not to leak enviornment variable memory, so... + +#include "toys.h" + +// In libc, populated by start code,used by getenv() and exec() and friends. +extern char **environ; + +// Returns the number of bytes taken by the environment variables. For use +// when calculating the maximum bytes of environment+argument data that can +// be passed to exec for find(1) and xargs(1). +long environ_bytes() +{ + long bytes = sizeof(char *); + char **ev; + + for (ev = environ; *ev; ev++) bytes += sizeof(char *) + strlen(*ev) + 1; + + return bytes; +} + +// This will clear the inherited environment if called first thing. +// Use this instead of envc so we keep track of what needs to be freed. +void xclearenv(void) +{ + toys.envc = 0; + *environ = 0; +} + +// Frees entries we set earlier. Use with libc getenv but not setenv/putenv. +// if name has an equals and !val, act like putenv (name=val must be malloced!) +// if !val unset name. (Name with = and val is an error) +void xsetenv(char *name, char *val) +{ + unsigned i, len, envc; + char *new; + + // If we haven't snapshot initial environment state yet, do so now. + if (!toys.envc) { + while (environ[toys.envc++]); + memcpy(new = xmalloc(((toys.envc|0xff)+1)*sizeof(char *)), + environ, toys.envc*sizeof(char *)); + environ = (void *)new; + } + + new = strchr(name, '='); + if (new) { + len = new-name; + if (val) error_exit("xsetenv %s to %s", name, val); + new = name; + } else { + len = strlen(name); + if (val) new = xmprintf("%s=%s", name, val); + } + + envc = toys.envc-1; + for (i = 0; environ[i]; i++) { + // Drop old entry, freeing as appropriate. Assumes no duplicates. + if (!memcmp(name, environ[i], len) && environ[i][len]=='=') { + if (i>=envc) free(environ[i]); + else { + char **delete = environ+i; + + // move old entries down, add at end of old data + toys.envc = envc--; + for (i=0; new ? i<envc : !!delete[i]; i++) delete[i] = delete[i+1]; + i = envc; + } + break; + } + } + + if (!new) return; + + // resize and null terminate if expanding + if (!environ[i]) { + len = i+1; + if (!(len&255)) environ = xrealloc(environ, len*sizeof(char *)); + environ[len] = 0; + } + environ[i] = new; +} + +// reset environment for a user, optionally clearing most of it +void reset_env(struct passwd *p, int clear) +{ + int i; + + if (clear) { + char *s, *stuff[] = {"TERM", "DISPLAY", "COLORTERM", "XAUTHORITY"}; + + for (i=0; i<ARRAY_LEN(stuff); i++) + stuff[i] = (s = getenv(stuff[i])) ? xmprintf("%s=%s", stuff[i], s) : 0; + xclearenv(); + for (i=0; i < ARRAY_LEN(stuff); i++) if (stuff[i]) xsetenv(stuff[i], 0); + if (chdir(p->pw_dir)) { + perror_msg("chdir %s", p->pw_dir); + xchdir("/"); + } + } else { + char **ev1, **ev2; + + // remove LD_*, IFS, ENV, and BASH_ENV from environment + for (ev1 = ev2 = environ;;) { + while (*ev2 && (strstart(ev2, "LD_") || strstart(ev2, "IFS=") || + strstart(ev2, "ENV=") || strstart(ev2, "BASH_ENV="))) ev2++; + if (!(*ev1++ = *ev2++)) break; + } + } + + setenv("PATH", _PATH_DEFPATH, 1); + setenv("HOME", p->pw_dir, 1); + setenv("SHELL", p->pw_shell, 1); + setenv("USER", p->pw_name, 1); + setenv("LOGNAME", p->pw_name, 1); +} @@ -1398,19 +1398,6 @@ void do_lines(int fd, char delim, void (*call)(char **pline, long len)) if (fd) fclose(fp); } -// Returns the number of bytes taken by the environment variables. For use -// when calculating the maximum bytes of environment+argument data that can -// be passed to exec for find(1) and xargs(1). -long environ_bytes() -{ - long bytes = sizeof(char *); - char **ev; - - for (ev = environ; *ev; ev++) bytes += sizeof(char *) + strlen(*ev) + 1; - - return bytes; -} - // Return unix time in milliseconds long long millitime(void) { @@ -1432,40 +1419,6 @@ char *format_iso_time(char *buf, size_t len, struct timespec *ts) return buf; } -// reset environment for a user, optionally clearing most of it -void reset_env(struct passwd *p, int clear) -{ - int i; - - if (clear) { - char *s, *stuff[] = {"TERM", "DISPLAY", "COLORTERM", "XAUTHORITY"}; - - for (i=0; i<ARRAY_LEN(stuff); i++) - stuff[i] = (s = getenv(stuff[i])) ? xmprintf("%s=%s", stuff[i], s) : 0; - clearenv(); - for (i=0; i < ARRAY_LEN(stuff); i++) if (stuff[i]) putenv(stuff[i]); - if (chdir(p->pw_dir)) { - perror_msg("chdir %s", p->pw_dir); - xchdir("/"); - } - } else { - char **ev1, **ev2; - - // remove LD_*, IFS, ENV, and BASH_ENV from environment - for (ev1 = ev2 = environ;;) { - while (*ev2 && (strstart(ev2, "LD_") || strstart(ev2, "IFS=") || - strstart(ev2, "ENV=") || strstart(ev2, "BASH_ENV="))) ev2++; - if (!(*ev1++ = *ev2++)) break; - } - } - - setenv("PATH", _PATH_DEFPATH, 1); - setenv("HOME", p->pw_dir, 1); - setenv("SHELL", p->pw_shell, 1); - setenv("USER", p->pw_name, 1); - setenv("LOGNAME", p->pw_name, 1); -} - // Syslog with the openlog/closelog, autodetecting daemon status via no tty void loggit(int priority, char *format, ...) @@ -261,7 +261,6 @@ int regexec0(regex_t *preg, char *string, long len, int nmatch, char *getusername(uid_t uid); char *getgroupname(gid_t gid); void do_lines(int fd, char delim, void (*call)(char **pline, long len)); -long environ_bytes(); long long millitime(void); char *format_iso_time(char *buf, size_t len, struct timespec *ts); void reset_env(struct passwd *p, int clear); @@ -272,6 +271,12 @@ void loggit(int priority, char *format, ...); #define HR_1000 4 // Use decimal instead of binary units int human_readable(char *buf, unsigned long long num, int style); +// env.c + +long environ_bytes(); +void xsetenv(char *name, char *val); +void xclearenv(void); + // linestack.c struct linestack { diff --git a/tests/env.test b/tests/env.test index 286fb36c..3098731d 100755 --- a/tests/env.test +++ b/tests/env.test @@ -18,3 +18,4 @@ testcmd "-0" "-i five=six seven=eight env -0 | sort -z" "five=six\0seven=eight\0 unset WALRUS BANANA LETTERS FILTER testcmd "early fail" '--oops 2> /dev/null ; echo $?' "125\n" "" "" +testcmd "why is this allowed" "=BLAH env | grep '^=BLAH\$'" "=BLAH\n" "" "" diff --git a/toys/posix/env.c b/toys/posix/env.c index 5c7bb789..d1bb580d 100644 --- a/toys/posix/env.c +++ b/toys/posix/env.c @@ -28,11 +28,10 @@ GLOBALS( struct arg_list *u; ); -extern char **environ; - void env_main(void) { char **ev = toys.optargs; + struct arg_list *u; // If first nonoption argument is "-" treat it as -i if (*ev && **ev == '-' && !(*ev)[1]) { @@ -40,21 +39,19 @@ void env_main(void) ev++; } - if (toys.optflags & FLAG_i) clearenv(); - while (TT.u) { - unsetenv(TT.u->arg); - TT.u = TT.u->next; - } + if (FLAG(i)) xclearenv(); + else for (u = TT.u; u; u = u->next) + if (strchr(u->arg, '=')) error_msg("bad -u %s", u->arg); + else xsetenv(u->arg, 0); for (; *ev; ev++) { - char *name = *ev, *val = strchr(name, '='); + char *val = strchr(*ev, '='); if (val) { *(val++) = 0; - setenv(name, val, 1); + xsetenv(*ev, val); } else xexec(ev); } - if (environ) for (ev = environ; *ev; ev++) - xprintf("%s%c", *ev, '\n'*!(toys.optflags&FLAG_0)); + for (ev = environ; *ev; ev++) xprintf("%s%c", *ev, '\n'*!FLAG(0)); } |