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Diffstat (limited to 'gdb/common/environ.c')
| -rw-r--r-- | gdb/common/environ.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/gdb/common/environ.c b/gdb/common/environ.c new file mode 100644 index 0000000..3145d01 --- /dev/null +++ b/gdb/common/environ.c @@ -0,0 +1,182 @@ +/* environ.c -- library for manipulating environments for GNU. + + Copyright (C) 1986-2017 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "common-defs.h" +#include "environ.h" +#include <algorithm> + + +/* Return a new environment object. */ + +struct gdb_environ * +make_environ (void) +{ + struct gdb_environ *e; + + e = XNEW (struct gdb_environ); + + e->allocated = 10; + e->vector = (char **) xmalloc ((e->allocated + 1) * sizeof (char *)); + e->vector[0] = 0; + return e; +} + +/* Free an environment and all the strings in it. */ + +void +free_environ (struct gdb_environ *e) +{ + char **vector = e->vector; + + while (*vector) + xfree (*vector++); + + xfree (e->vector); + xfree (e); +} + +/* Copy the environment given to this process into E. + Also copies all the strings in it, so we can be sure + that all strings in these environments are safe to free. */ + +void +init_environ (struct gdb_environ *e) +{ + extern char **environ; + int i; + + if (environ == NULL) + return; + + for (i = 0; environ[i]; i++) /*EMPTY */ ; + + if (e->allocated < i) + { + e->allocated = std::max (i, e->allocated + 10); + e->vector = (char **) xrealloc ((char *) e->vector, + (e->allocated + 1) * sizeof (char *)); + } + + memcpy (e->vector, environ, (i + 1) * sizeof (char *)); + + while (--i >= 0) + { + int len = strlen (e->vector[i]); + char *newobj = (char *) xmalloc (len + 1); + + memcpy (newobj, e->vector[i], len + 1); + e->vector[i] = newobj; + } +} + +/* Return the vector of environment E. + This is used to get something to pass to execve. */ + +char ** +environ_vector (struct gdb_environ *e) +{ + return e->vector; +} + +/* Return the value in environment E of variable VAR. */ + +char * +get_in_environ (const struct gdb_environ *e, const char *var) +{ + int len = strlen (var); + char **vector = e->vector; + char *s; + + for (; (s = *vector) != NULL; vector++) + if (strncmp (s, var, len) == 0 && s[len] == '=') + return &s[len + 1]; + + return 0; +} + +/* Store the value in E of VAR as VALUE. */ + +void +set_in_environ (struct gdb_environ *e, const char *var, const char *value) +{ + int i; + int len = strlen (var); + char **vector = e->vector; + char *s; + + for (i = 0; (s = vector[i]) != NULL; i++) + if (strncmp (s, var, len) == 0 && s[len] == '=') + break; + + if (s == 0) + { + if (i == e->allocated) + { + e->allocated += 10; + vector = (char **) xrealloc ((char *) vector, + (e->allocated + 1) * sizeof (char *)); + e->vector = vector; + } + vector[i + 1] = 0; + } + else + xfree (s); + + s = (char *) xmalloc (len + strlen (value) + 2); + strcpy (s, var); + strcat (s, "="); + strcat (s, value); + vector[i] = s; + + /* This used to handle setting the PATH and GNUTARGET variables + specially. The latter has been replaced by "set gnutarget" + (which has worked since GDB 4.11). The former affects searching + the PATH to find SHELL, and searching the PATH to find the + argument of "symbol-file" or "exec-file". Maybe we should have + some kind of "set exec-path" for that. But in any event, having + "set env" affect anything besides the inferior is a bad idea. + What if we want to change the environment we pass to the program + without afecting GDB's behavior? */ + + return; +} + +/* Remove the setting for variable VAR from environment E. */ + +void +unset_in_environ (struct gdb_environ *e, const char *var) +{ + int len = strlen (var); + char **vector = e->vector; + char *s; + + for (; (s = *vector) != NULL; vector++) + { + if (strncmp (s, var, len) == 0 && s[len] == '=') + { + xfree (s); + /* Walk through the vector, shuffling args down by one, including + the NULL terminator. Can't use memcpy() here since the regions + overlap, and memmove() might not be available. */ + while ((vector[0] = vector[1]) != NULL) + { + vector++; + } + break; + } + } +} |