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-rw-r--r--libshouldbeinlibc/=envz.c171
-rw-r--r--libshouldbeinlibc/=envz.h55
2 files changed, 226 insertions, 0 deletions
diff --git a/libshouldbeinlibc/=envz.c b/libshouldbeinlibc/=envz.c
new file mode 100644
index 00000000..95140087
--- /dev/null
+++ b/libshouldbeinlibc/=envz.c
@@ -0,0 +1,171 @@
+/* Routines for dealing with '\0' separated environment vectors
+
+ Copyright (C) 1995 Free Software Foundation, Inc.
+
+ Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+ 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 2, 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, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <malloc.h>
+#include <string.h>
+
+#include "envz.h"
+
+/* The character separating names from values in an envz. */
+#define SEP '='
+
+/* Returns a pointer to the entry in ENVZ for NAME, or 0 if there is none.
+ If NAME contains the separator character, only the portion before it is
+ used in the comparison. */
+char *
+envz_entry (char *envz, unsigned envz_len, char *name)
+{
+ while (envz_len)
+ {
+ char *p = name;
+ char *entry = envz; /* Start of this entry. */
+
+ /* See how far NAME and ENTRY match. */
+ while (envz_len && *p == *envz && *p && *p != SEP)
+ p++, envz++, envz_len--;
+
+ if ((*envz == '\0' || *envz == SEP) && (*p == '\0' || *p == SEP))
+ /* Bingo! */
+ return entry;
+
+ /* No match, skip to the next entry. */
+ while (envz_len && *envz)
+ envz++, envz_len--;
+ if (envz_len)
+ envz++, envz_len--; /* skip '\0' */
+ }
+
+ return 0;
+}
+
+/* Returns a pointer to the value portion of the entry in ENVZ for NAME, or 0
+ if there is none. */
+char *
+envz_get (char *envz, unsigned envz_len, char *name)
+{
+ char *entry = envz_entry (envz, envz_len, name);
+ if (entry)
+ {
+ while (*entry && *entry != SEP)
+ entry++;
+ if (*entry)
+ entry++;
+ else
+ entry = 0; /* A null entry. */
+ }
+ return entry;
+}
+
+/* Remove the entry for NAME from ENVZ & ENVZ_LEN, if any. */
+void
+envz_remove (char **envz, unsigned *envz_len, char *name)
+{
+ char *entry = envz_entry (*envz, *envz_len, name);
+ if (entry)
+ argz_delete (envz, envz_len, entry);
+}
+
+/* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN. If an entry
+ with the same name already exists in ENVZ, it is removed. If VALUE is
+ NULL, then the new entry will a special null one, for which envz_get will
+ return NULL, although envz_entry will still return an entry; this is handy
+ because when merging with another envz, the null entry can override an
+ entry in the other one. Null entries can be removed with envz_strip (). */
+error_t
+envz_add (char **envz, unsigned *envz_len, char *name, char *value)
+{
+ envz_remove (envz, envz_len, name);
+
+ if (value)
+ /* Add the new value, if there is one. */
+ {
+ unsigned name_len = strlen (name);
+ unsigned value_len = strlen (value);
+ unsigned old_envz_len = *envz_len;
+ unsigned new_envz_len = old_envz_len + name_len + 1 + value_len + 1;
+ char *new_envz = realloc (*envz, new_envz_len);
+
+ if (new_envz)
+ {
+ bcopy (name, new_envz + old_envz_len, name_len);
+ new_envz[old_envz_len + name_len] = SEP;
+ bcopy (value, new_envz + old_envz_len + name_len + 1, value_len);
+ new_envz[new_envz_len - 1] = 0;
+
+ *envz = new_envz;
+ *envz_len = new_envz_len;
+
+ return 0;
+ }
+ else
+ return ENOMEM;
+ }
+ else
+ /* Add a null entry. */
+ return argz_add (envz, envz_len, name);
+}
+
+/* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add(). If
+ OVERRIDE is true, then values in ENVZ2 will supercede those with the same
+ name in ENV, otherwise not. */
+error_t
+envz_merge (char **envz, unsigned *envz_len, char *envz2, unsigned envz2_len,
+ int override)
+{
+ error_t err = 0;
+
+ while (envz2_len && ! err)
+ {
+ char *old = envz_entry (*envz, *envz_len, envz2);
+ char new_len = strlen (envz2) + 1;
+
+ if (! old)
+ err = argz_append (envz, envz_len, envz2, new_len);
+ else if (override)
+ {
+ argz_delete (envz, envz_len, old);
+ err = argz_append (envz, envz_len, envz2, new_len);
+ }
+
+ envz2 += new_len;
+ envz2_len -= new_len;
+ }
+
+ return err;
+}
+
+/* Remove null entries. */
+void
+envz_strip (char **envz, unsigned *envz_len)
+{
+ char *entry = *envz;
+ unsigned left = *envz_len;
+ while (left)
+ {
+ unsigned entry_len = strlen (entry) + 1;
+ left -= entry_len;
+ if (! index (entry, SEP))
+ /* Null entry. */
+ bcopy (entry, entry + entry_len, left);
+ else
+ entry += entry_len;
+ }
+ *envz_len = entry - *envz;
+}
diff --git a/libshouldbeinlibc/=envz.h b/libshouldbeinlibc/=envz.h
new file mode 100644
index 00000000..55224c72
--- /dev/null
+++ b/libshouldbeinlibc/=envz.h
@@ -0,0 +1,55 @@
+/* Routines for dealing with '\0' separated environment vectors
+
+ Copyright (C) 1995 Free Software Foundation, Inc.
+
+ Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+ 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 2, 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, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#ifndef __ENVZ_H__
+#define __ENVZ_H__
+
+#include <errno.h>
+
+/* Envz's are argz's too, and should be created etc., using the same
+ routines. */
+#include <argz.h>
+
+/* Returns a pointer to the entry in ENVZ for NAME, or 0 if there is none. */
+char *envz_entry (char *envz, unsigned envz_len, char *name);
+
+/* Returns a pointer to the value portion of the entry in ENVZ for NAME, or 0
+ if there is none. */
+char *envz_get (char *envz, unsigned envz_len, char *name);
+
+/* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN. If an entry
+ with the same name already exists in ENVZ, it is removed. If VALUE is
+ NULL, then the new entry will a special null one, for which envz_get will
+ return NULL, although envz_entry will still return an entry; this is handy
+ because when merging with another envz, the null entry can override an
+ entry in the other one. Null entries can be removed with envz_strip (). */
+error_t envz_add (char **envz, unsigned *envz_len, char *name, char *value);
+
+/* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add(). If
+ OVERRIDE is true, then values in ENVZ2 will supercede those with the same
+ name in ENV, otherwise not. */
+error_t
+envz_merge (char **envz, unsigned *envz_len, char *envz2, unsigned envz2_len,
+ int override);
+
+/* Remove null entries. */
+void envz_strip (char **envz, unsigned *envz_len);
+
+#endif /* __ENVZ_H__ */
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