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-rw-r--r--sebhbsd/freebsd/contrib/ntp/sntp/libopts/text_mmap.c379
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diff --git a/sebhbsd/freebsd/contrib/ntp/sntp/libopts/text_mmap.c b/sebhbsd/freebsd/contrib/ntp/sntp/libopts/text_mmap.c
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index 0000000..07c0bf1
--- /dev/null
+++ b/sebhbsd/freebsd/contrib/ntp/sntp/libopts/text_mmap.c
@@ -0,0 +1,379 @@
+/**
+ * @file text_mmap.c
+ *
+ * Map a text file, ensuring the text always has an ending NUL byte.
+ *
+ * @addtogroup autoopts
+ * @{
+ */
+/*
+ * This file is part of AutoOpts, a companion to AutoGen.
+ * AutoOpts is free software.
+ * AutoOpts is Copyright (C) 1992-2015 by Bruce Korb - all rights reserved
+ *
+ * AutoOpts is available under any one of two licenses. The license
+ * in use must be one of these two and the choice is under the control
+ * of the user of the license.
+ *
+ * The GNU Lesser General Public License, version 3 or later
+ * See the files "COPYING.lgplv3" and "COPYING.gplv3"
+ *
+ * The Modified Berkeley Software Distribution License
+ * See the file "COPYING.mbsd"
+ *
+ * These files have the following sha256 sums:
+ *
+ * 8584710e9b04216a394078dc156b781d0b47e1729104d666658aecef8ee32e95 COPYING.gplv3
+ * 4379e7444a0e2ce2b12dd6f5a52a27a4d02d39d247901d3285c88cf0d37f477b COPYING.lgplv3
+ * 13aa749a5b0a454917a944ed8fffc530b784f5ead522b1aacaf4ec8aa55a6239 COPYING.mbsd
+ */
+#if defined(HAVE_MMAP)
+# ifndef MAP_ANONYMOUS
+# ifdef MAP_ANON
+# define MAP_ANONYMOUS MAP_ANON
+# endif
+# endif
+
+# if ! defined(MAP_ANONYMOUS) && ! defined(HAVE_DEV_ZERO)
+ /*
+ * We must have either /dev/zero or anonymous mapping for
+ * this to work.
+ */
+# undef HAVE_MMAP
+
+# else
+# ifdef _SC_PAGESIZE
+# define GETPAGESIZE() sysconf(_SC_PAGESIZE)
+# else
+# define GETPAGESIZE() getpagesize()
+# endif
+# endif
+#endif
+
+/*
+ * Some weird systems require that a specifically invalid FD number
+ * get passed in as an argument value. Which value is that? Well,
+ * as everybody knows, if open(2) fails, it returns -1, so that must
+ * be the value. :)
+ */
+#define AO_INVALID_FD -1
+
+#define FILE_WRITABLE(_prt,_flg) \
+ ( (_prt & PROT_WRITE) \
+ && ((_flg & (MAP_SHARED|MAP_PRIVATE)) == MAP_SHARED))
+#define MAP_FAILED_PTR (VOIDP(MAP_FAILED))
+
+/**
+ * Load the contents of a text file. There are two separate implementations,
+ * depending up on whether mmap(3) is available.
+ *
+ * If not available, malloc the file length plus one byte. Read it in
+ * and NUL terminate.
+ *
+ * If available, first check to see if the text file size is a multiple of a
+ * page size. If it is, map the file size plus an extra page from either
+ * anonymous memory or from /dev/zero. Then map the file text on top of the
+ * first pages of the anonymous/zero pages. Otherwise, just map the file
+ * because there will be NUL bytes provided at the end.
+ *
+ * @param mapinfo a structure holding everything we need to know
+ * about the mapping.
+ *
+ * @param pzFile name of the file, for error reporting.
+ */
+static void
+load_text_file(tmap_info_t * mapinfo, char const * pzFile)
+{
+#if ! defined(HAVE_MMAP)
+ mapinfo->txt_data = AGALOC(mapinfo->txt_size+1, "file text");
+ if (mapinfo->txt_data == NULL) {
+ mapinfo->txt_errno = ENOMEM;
+ return;
+ }
+
+ {
+ size_t sz = mapinfo->txt_size;
+ char * pz = mapinfo->txt_data;
+
+ while (sz > 0) {
+ ssize_t rdct = read(mapinfo->txt_fd, pz, sz);
+ if (rdct <= 0) {
+ mapinfo->txt_errno = errno;
+ fserr_warn("libopts", "read", pzFile);
+ free(mapinfo->txt_data);
+ return;
+ }
+
+ pz += rdct;
+ sz -= rdct;
+ }
+
+ *pz = NUL;
+ }
+
+ mapinfo->txt_errno = 0;
+
+#else /* HAVE mmap */
+ size_t const pgsz = (size_t)GETPAGESIZE();
+ void * map_addr = NULL;
+
+ (void)pzFile;
+
+ mapinfo->txt_full_size = (mapinfo->txt_size + pgsz) & ~(pgsz - 1);
+ if (mapinfo->txt_full_size == (mapinfo->txt_size + pgsz)) {
+ /*
+ * The text is a multiple of a page boundary. We must map an
+ * extra page so the text ends with a NUL.
+ */
+#if defined(MAP_ANONYMOUS)
+ map_addr = mmap(NULL, mapinfo->txt_full_size, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, AO_INVALID_FD, 0);
+#else
+ mapinfo->txt_zero_fd = open("/dev/zero", O_RDONLY);
+
+ if (mapinfo->txt_zero_fd == AO_INVALID_FD) {
+ mapinfo->txt_errno = errno;
+ return;
+ }
+ map_addr = mmap(NULL, mapinfo->txt_full_size, PROT_READ|PROT_WRITE,
+ MAP_PRIVATE, mapinfo->txt_zero_fd, 0);
+#endif
+ if (map_addr == MAP_FAILED_PTR) {
+ mapinfo->txt_errno = errno;
+ return;
+ }
+ mapinfo->txt_flags |= MAP_FIXED;
+ }
+
+ mapinfo->txt_data =
+ mmap(map_addr, mapinfo->txt_size, mapinfo->txt_prot,
+ mapinfo->txt_flags, mapinfo->txt_fd, 0);
+
+ if (mapinfo->txt_data == MAP_FAILED_PTR)
+ mapinfo->txt_errno = errno;
+#endif /* HAVE_MMAP */
+}
+
+/**
+ * Make sure all the parameters are correct: we have a file name that
+ * is a text file that we can read.
+ *
+ * @param fname the text file to map
+ * @param prot the memory protections requested (read/write/etc.)
+ * @param flags mmap flags
+ * @param mapinfo a structure holding everything we need to know
+ * about the mapping.
+ */
+static void
+validate_mmap(char const * fname, int prot, int flags, tmap_info_t * mapinfo)
+{
+ memset(mapinfo, 0, sizeof(*mapinfo));
+#if defined(HAVE_MMAP) && ! defined(MAP_ANONYMOUS)
+ mapinfo->txt_zero_fd = AO_INVALID_FD;
+#endif
+ mapinfo->txt_fd = AO_INVALID_FD;
+ mapinfo->txt_prot = prot;
+ mapinfo->txt_flags = flags;
+
+ /*
+ * Map mmap flags and protections into open flags and do the open.
+ */
+ {
+ /*
+ * See if we will be updating the file. If we can alter the memory
+ * and if we share the data and we are *not* copy-on-writing the data,
+ * then our updates will show in the file, so we must open with
+ * write access.
+ */
+ int o_flag = FILE_WRITABLE(prot, flags) ? O_RDWR : O_RDONLY;
+
+ /*
+ * If you're not sharing the file and you are writing to it,
+ * then don't let anyone else have access to the file.
+ */
+ if (((flags & MAP_SHARED) == 0) && (prot & PROT_WRITE))
+ o_flag |= O_EXCL;
+
+ mapinfo->txt_fd = open(fname, o_flag);
+ if (mapinfo->txt_fd < 0) {
+ mapinfo->txt_errno = errno;
+ mapinfo->txt_fd = AO_INVALID_FD;
+ return;
+ }
+ }
+
+ /*
+ * Make sure we can stat the regular file. Save the file size.
+ */
+ {
+ struct stat sb;
+ if (fstat(mapinfo->txt_fd, &sb) != 0) {
+ mapinfo->txt_errno = errno;
+ close(mapinfo->txt_fd);
+ return;
+ }
+
+ if (! S_ISREG(sb.st_mode)) {
+ mapinfo->txt_errno = errno = EINVAL;
+ close(mapinfo->txt_fd);
+ return;
+ }
+
+ mapinfo->txt_size = (size_t)sb.st_size;
+ }
+
+ if (mapinfo->txt_fd == AO_INVALID_FD)
+ mapinfo->txt_errno = errno;
+}
+
+/**
+ * Close any files opened by the mapping.
+ *
+ * @param mi a structure holding everything we need to know about the map.
+ */
+static void
+close_mmap_files(tmap_info_t * mi)
+{
+ if (mi->txt_fd == AO_INVALID_FD)
+ return;
+
+ close(mi->txt_fd);
+ mi->txt_fd = AO_INVALID_FD;
+
+#if defined(HAVE_MMAP) && ! defined(MAP_ANONYMOUS)
+ if (mi->txt_zero_fd == AO_INVALID_FD)
+ return;
+
+ close(mi->txt_zero_fd);
+ mi->txt_zero_fd = AO_INVALID_FD;
+#endif
+}
+
+/*=export_func text_mmap
+ * private:
+ *
+ * what: map a text file with terminating NUL
+ *
+ * arg: char const *, pzFile, name of the file to map
+ * arg: int, prot, mmap protections (see mmap(2))
+ * arg: int, flags, mmap flags (see mmap(2))
+ * arg: tmap_info_t *, mapinfo, returned info about the mapping
+ *
+ * ret-type: void *
+ * ret-desc: The mmaped data address
+ *
+ * doc:
+ *
+ * This routine will mmap a file into memory ensuring that there is at least
+ * one @file{NUL} character following the file data. It will return the
+ * address where the file contents have been mapped into memory. If there is a
+ * problem, then it will return @code{MAP_FAILED} and set @code{errno}
+ * appropriately.
+ *
+ * The named file does not exist, @code{stat(2)} will set @code{errno} as it
+ * will. If the file is not a regular file, @code{errno} will be
+ * @code{EINVAL}. At that point, @code{open(2)} is attempted with the access
+ * bits set appropriately for the requested @code{mmap(2)} protections and flag
+ * bits. On failure, @code{errno} will be set according to the documentation
+ * for @code{open(2)}. If @code{mmap(2)} fails, @code{errno} will be set as
+ * that routine sets it. If @code{text_mmap} works to this point, a valid
+ * address will be returned, but there may still be ``issues''.
+ *
+ * If the file size is not an even multiple of the system page size, then
+ * @code{text_map} will return at this point and @code{errno} will be zero.
+ * Otherwise, an anonymous map is attempted. If not available, then an attempt
+ * is made to @code{mmap(2)} @file{/dev/zero}. If any of these fail, the
+ * address of the file's data is returned, bug @code{no} @file{NUL} characters
+ * are mapped after the end of the data.
+ *
+ * see: mmap(2), open(2), stat(2)
+ *
+ * err: Any error code issued by mmap(2), open(2), stat(2) is possible.
+ * Additionally, if the specified file is not a regular file, then
+ * errno will be set to @code{EINVAL}.
+ *
+ * example:
+ * #include <mylib.h>
+ * tmap_info_t mi;
+ * int no_nul;
+ * void * data = text_mmap("file", PROT_WRITE, MAP_PRIVATE, &mi);
+ * if (data == MAP_FAILED) return;
+ * no_nul = (mi.txt_size == mi.txt_full_size);
+ * << use the data >>
+ * text_munmap(&mi);
+=*/
+void *
+text_mmap(char const * pzFile, int prot, int flags, tmap_info_t * mi)
+{
+ validate_mmap(pzFile, prot, flags, mi);
+ if (mi->txt_errno != 0)
+ return MAP_FAILED_PTR;
+
+ load_text_file(mi, pzFile);
+
+ if (mi->txt_errno == 0)
+ return mi->txt_data;
+
+ close_mmap_files(mi);
+
+ errno = mi->txt_errno;
+ mi->txt_data = MAP_FAILED_PTR;
+ return mi->txt_data;
+}
+
+
+/*=export_func text_munmap
+ * private:
+ *
+ * what: unmap the data mapped in by text_mmap
+ *
+ * arg: tmap_info_t *, mapinfo, info about the mapping
+ *
+ * ret-type: int
+ * ret-desc: -1 or 0. @code{errno} will have the error code.
+ *
+ * doc:
+ *
+ * This routine will unmap the data mapped in with @code{text_mmap} and close
+ * the associated file descriptors opened by that function.
+ *
+ * see: munmap(2), close(2)
+ *
+ * err: Any error code issued by munmap(2) or close(2) is possible.
+=*/
+int
+text_munmap(tmap_info_t * mi)
+{
+ errno = 0;
+
+#ifdef HAVE_MMAP
+ (void)munmap(mi->txt_data, mi->txt_full_size);
+
+#else /* don't HAVE_MMAP */
+ /*
+ * IF the memory is writable *AND* it is not private (copy-on-write)
+ * *AND* the memory is "sharable" (seen by other processes)
+ * THEN rewrite the data. Emulate mmap visibility.
+ */
+ if ( FILE_WRITABLE(mi->txt_prot, mi->txt_flags)
+ && (lseek(mi->txt_fd, 0, SEEK_SET) >= 0) ) {
+ write(mi->txt_fd, mi->txt_data, mi->txt_size);
+ }
+
+ free(mi->txt_data);
+#endif /* HAVE_MMAP */
+
+ mi->txt_errno = errno;
+ close_mmap_files(mi);
+
+ return mi->txt_errno;
+}
+
+/** @}
+ *
+ * Local Variables:
+ * mode: C
+ * c-file-style: "stroustrup"
+ * indent-tabs-mode: nil
+ * End:
+ * end of autoopts/text_mmap.c */
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