diff options
Diffstat (limited to 'tools/build/fixdep.c')
| -rw-r--r-- | tools/build/fixdep.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/tools/build/fixdep.c b/tools/build/fixdep.c new file mode 100644 index 000000000..2501fea7a --- /dev/null +++ b/tools/build/fixdep.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * "Optimize" a list of dependencies as spit out by gcc -MD + * for the build framework. + * + * Original author: + * Copyright 2002 by Kai Germaschewski <kai.germaschewski@gmx.de> + * + * This code has been borrowed from kbuild's fixdep (scripts/basic/fixdep.c), + * Please check it for detailed explanation. This fixdep borow only the + * base transformation of dependecies without the CONFIG mangle. + */ + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/mman.h> +#include <unistd.h> +#include <fcntl.h> +#include <string.h> +#include <stdlib.h> +#include <stdio.h> +#include <limits.h> + +char *target; +char *depfile; +char *cmdline; + +static void usage(void) +{ + fprintf(stderr, "Usage: fixdep <depfile> <target> <cmdline>\n"); + exit(1); +} + +/* + * Print out the commandline prefixed with cmd_<target filename> := + */ +static void print_cmdline(void) +{ + printf("cmd_%s := %s\n\n", target, cmdline); +} + +/* + * Important: The below generated source_foo.o and deps_foo.o variable + * assignments are parsed not only by make, but also by the rather simple + * parser in scripts/mod/sumversion.c. + */ +static void parse_dep_file(void *map, size_t len) +{ + char *m = map; + char *end = m + len; + char *p; + char s[PATH_MAX]; + int is_target, has_target = 0; + int saw_any_target = 0; + int is_first_dep = 0; + + while (m < end) { + /* Skip any "white space" */ + while (m < end && (*m == ' ' || *m == '\\' || *m == '\n')) + m++; + /* Find next "white space" */ + p = m; + while (p < end && *p != ' ' && *p != '\\' && *p != '\n') + p++; + /* Is the token we found a target name? */ + is_target = (*(p-1) == ':'); + /* Don't write any target names into the dependency file */ + if (is_target) { + /* The /next/ file is the first dependency */ + is_first_dep = 1; + has_target = 1; + } else if (has_target) { + /* Save this token/filename */ + memcpy(s, m, p-m); + s[p - m] = 0; + + /* + * Do not list the source file as dependency, + * so that kbuild is not confused if a .c file + * is rewritten into .S or vice versa. Storing + * it in source_* is needed for modpost to + * compute srcversions. + */ + if (is_first_dep) { + /* + * If processing the concatenation of + * multiple dependency files, only + * process the first target name, which + * will be the original source name, + * and ignore any other target names, + * which will be intermediate temporary + * files. + */ + if (!saw_any_target) { + saw_any_target = 1; + printf("source_%s := %s\n\n", + target, s); + printf("deps_%s := \\\n", + target); + } + is_first_dep = 0; + } else + printf(" %s \\\n", s); + } + /* + * Start searching for next token immediately after the first + * "whitespace" character that follows this token. + */ + m = p + 1; + } + + if (!saw_any_target) { + fprintf(stderr, "fixdep: parse error; no targets found\n"); + exit(1); + } + + printf("\n%s: $(deps_%s)\n\n", target, target); + printf("$(deps_%s):\n", target); +} + +static void print_deps(void) +{ + struct stat st; + int fd; + void *map; + + fd = open(depfile, O_RDONLY); + if (fd < 0) { + fprintf(stderr, "fixdep: error opening depfile: "); + perror(depfile); + exit(2); + } + if (fstat(fd, &st) < 0) { + fprintf(stderr, "fixdep: error fstat'ing depfile: "); + perror(depfile); + exit(2); + } + if (st.st_size == 0) { + fprintf(stderr, "fixdep: %s is empty\n", depfile); + close(fd); + return; + } + map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + if ((long) map == -1) { + perror("fixdep: mmap"); + close(fd); + return; + } + + parse_dep_file(map, st.st_size); + + munmap(map, st.st_size); + + close(fd); +} + +int main(int argc, char **argv) +{ + if (argc != 4) + usage(); + + depfile = argv[1]; + target = argv[2]; + cmdline = argv[3]; + + print_cmdline(); + print_deps(); + + return 0; +} |