From f277b7b051893647ae88127d55765b3d1c731796 Mon Sep 17 00:00:00 2001 From: kib Date: Mon, 12 Mar 2012 12:16:08 +0000 Subject: [PATCH 136/175] Rtld on diet part 2: Do not use stdio for libmap.conf read. Directly map the file and parse lines from the mappings. Reviewed by: kan MFC after: 3 weeks git-svn-id: http://svn.freebsd.org/base/head@232862 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f (cherry picked from commit 1c288bffa5999648b48ce11ad768abec4995c452) Signed-off-by: Xin Li --- libexec/rtld-elf/libmap.c | 148 +++++++++++++++++++++++---------------------- 1 file changed, 76 insertions(+), 72 deletions(-) diff --git a/libexec/rtld-elf/libmap.c b/libexec/rtld-elf/libmap.c index 7f55c9d..92a0469 100644 --- a/libexec/rtld-elf/libmap.c +++ b/libexec/rtld-elf/libmap.c @@ -2,11 +2,14 @@ * $FreeBSD$ */ -#include -#include -#include -#include #include +#include +#include +#include +#include +#include +#include +#include #include "debug.h" #include "rtld.h" @@ -25,7 +28,6 @@ TAILQ_HEAD(lm_list, lm); struct lm { char *f; char *t; - TAILQ_ENTRY(lm) lm_link; }; @@ -37,17 +39,15 @@ struct lmp { TAILQ_ENTRY(lmp) lmp_link; }; -static int lm_count; +static int lm_count; -static void lmc_parse (FILE *); -static void lm_add (const char *, const char *, const char *); -static void lm_free (struct lm_list *); -static char * lml_find (struct lm_list *, const char *); -static struct lm_list * lmp_find (const char *); -static struct lm_list * lmp_init (char *); -static const char * quickbasename (const char *); -static int readstrfn (void * cookie, char *buf, int len); -static int closestrfn (void * cookie); +static void lmc_parse(char *, size_t); +static void lm_add(const char *, const char *, const char *); +static void lm_free(struct lm_list *); +static char *lml_find(struct lm_list *, const char *); +static struct lm_list *lmp_find(const char *); +static struct lm_list *lmp_init(char *); +static const char *quickbasename(const char *); #define iseol(c) (((c) == '#') || ((c) == '\0') || \ ((c) == '\n') || ((c) == '\r')) @@ -59,56 +59,88 @@ static int closestrfn (void * cookie); #define rtld_isspace(c) ((c) == ' ' || (c) == '\t') int -lm_init (char *libmap_override) +lm_init(char *libmap_override) { - FILE *fp; - - dbg("%s(\"%s\")", __func__, libmap_override); + struct stat st; + char *lm_map, *p; + int fd; + dbg("lm_init(\"%s\")", libmap_override); TAILQ_INIT(&lmp_head); - fp = fopen(_PATH_LIBMAP_CONF, "r"); - if (fp) { - lmc_parse(fp); - fclose(fp); + fd = open(_PATH_LIBMAP_CONF, O_RDONLY); + if (fd == -1) { + dbg("lm_init: open(\"%s\") failed, %s", _PATH_LIBMAP_CONF, + strerror(errno)); + goto override; + } + if (fstat(fd, &st) == -1) { + close(fd); + dbg("lm_init: fstat(\"%s\") failed, %s", _PATH_LIBMAP_CONF, + strerror(errno)); + goto override; } + lm_map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + if (lm_map == (const char *)MAP_FAILED) { + close(fd); + dbg("lm_init: mmap(\"%s\") failed, %s", _PATH_LIBMAP_CONF, + strerror(errno)); + goto override; + } + close(fd); + lmc_parse(lm_map, st.st_size); + munmap(lm_map, st.st_size); +override: if (libmap_override) { - char *p; - /* do some character replacement to make $LIBMAP look like a - text file, then "open" it with funopen */ + /* + * Do some character replacement to make $LIBMAP look + * like a text file, then parse it. + */ libmap_override = xstrdup(libmap_override); - for (p = libmap_override; *p; p++) { switch (*p) { - case '=': - *p = ' '; break; - case ',': - *p = '\n'; break; + case '=': + *p = ' '; + break; + case ',': + *p = '\n'; + break; } } - fp = funopen(libmap_override, readstrfn, NULL, NULL, closestrfn); - if (fp) { - lmc_parse(fp); - fclose(fp); - } + lmc_parse(p, strlen(p)); + free(p); } return (lm_count == 0); } static void -lmc_parse (FILE *fp) +lmc_parse(char *lm_p, size_t lm_len) { - char *cp; - char *f, *t, *c, *p; - char prog[MAXPATHLEN]; - char line[MAXPATHLEN + 2]; - - dbg("%s(%p)", __func__, fp); + char *cp, *f, *t, *c, *p; + char prog[MAXPATHLEN]; + char line[MAXPATHLEN + 2]; + size_t cnt; + int i; + cnt = 0; p = NULL; - while ((cp = fgets(line, MAXPATHLEN + 1, fp)) != NULL) { + while (cnt < lm_len) { + i = 0; + while (lm_p[cnt] != '\n' && cnt < lm_len && + i < sizeof(line) - 1) { + line[i] = lm_p[cnt]; + cnt++; + i++; + } + line[i] = '\0'; + while (lm_p[cnt] != '\n' && cnt < lm_len) + cnt++; + /* skip over nl */ + cnt++; + + cp = &line[0]; t = f = c = NULL; /* Skip over leading space */ @@ -344,31 +376,3 @@ quickbasename (const char *path) } return (p); } - -static int -readstrfn(void * cookie, char *buf, int len) -{ - static char *current; - static int left; - int copied; - - copied = 0; - if (!current) { - current = cookie; - left = strlen(cookie); - } - while (*current && left && len) { - *buf++ = *current++; - left--; - len--; - copied++; - } - return copied; -} - -static int -closestrfn(void * cookie) -{ - free(cookie); - return 0; -} -- 1.7.9.4