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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#include <sys/types.h>#include <sys/stat.h>#include <unistd.h>#include <fcntl.h>#include <string.h>#include <stdbool.h>#include <stdlib.h>#include <stdio.h>#include <ctype.h>
#include <xalloc.h>
static void usage(void){ fprintf(stderr, "Usage: fixdep <depfile> <target> <cmdline>\n"); exit(1);}
struct item { struct item *next; unsigned int len; unsigned int hash; char name[];};
#define HASHSZ 256static struct item *config_hashtab[HASHSZ], *file_hashtab[HASHSZ];
static unsigned int strhash(const char *str, unsigned int sz){ /* fnv32 hash */ unsigned int i, hash = 2166136261U;
for (i = 0; i < sz; i++) hash = (hash ^ str[i]) * 0x01000193; return hash;}
/* * Add a new value to the configuration string. */static void add_to_hashtable(const char *name, int len, unsigned int hash, struct item *hashtab[]){ struct item *aux;
aux = xmalloc(sizeof(*aux) + len); memcpy(aux->name, name, len); aux->len = len; aux->hash = hash; aux->next = hashtab[hash % HASHSZ]; hashtab[hash % HASHSZ] = aux;}
/* * Lookup a string in the hash table. If found, just return true. * If not, add it to the hashtable and return false. */static bool in_hashtable(const char *name, int len, struct item *hashtab[]){ struct item *aux; unsigned int hash = strhash(name, len);
for (aux = hashtab[hash % HASHSZ]; aux; aux = aux->next) { if (aux->hash == hash && aux->len == len && memcmp(aux->name, name, len) == 0) return true; }
add_to_hashtable(name, len, hash, hashtab);
return false;}
/* * Record the use of a CONFIG_* word. */static void use_config(const char *m, int slen){ if (in_hashtable(m, slen, config_hashtab)) return;
/* Print out a dependency path from a symbol name. */ printf(" $(wildcard include/config/%.*s) \\\n", slen, m);}
/* test if s ends in sub */static int str_ends_with(const char *s, int slen, const char *sub){ int sublen = strlen(sub);
if (sublen > slen) return 0;
return !memcmp(s + slen - sublen, sub, sublen);}
static void parse_config_file(const char *p){ const char *q, *r; const char *start = p;
while ((p = strstr(p, "CONFIG_"))) { if (p > start && (isalnum(p[-1]) || p[-1] == '_')) { p += 7; continue; } p += 7; q = p; while (isalnum(*q) || *q == '_') q++; if (str_ends_with(p, q - p, "_MODULE")) r = q - 7; else r = q; if (r > p) use_config(p, r - p); p = q; }}
static void *read_file(const char *filename){ struct stat st; int fd; char *buf;
fd = open(filename, O_RDONLY); if (fd < 0) { fprintf(stderr, "fixdep: error opening file: "); perror(filename); exit(2); } if (fstat(fd, &st) < 0) { fprintf(stderr, "fixdep: error fstat'ing file: "); perror(filename); exit(2); } buf = xmalloc(st.st_size + 1); if (read(fd, buf, st.st_size) != st.st_size) { perror("fixdep: read"); exit(2); } buf[st.st_size] = '\0'; close(fd);
return buf;}
/* Ignore certain dependencies */static int is_ignored_file(const char *s, int len){ return str_ends_with(s, len, "include/generated/autoconf.h");}
/* Do not parse these files */static int is_no_parse_file(const char *s, int len){ /* rustc may list binary files in dep-info */ return str_ends_with(s, len, ".rlib") || str_ends_with(s, len, ".rmeta") || str_ends_with(s, len, ".so");}
/* * 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(char *p, const char *target){ bool saw_any_target = false; bool is_target = true; bool is_source = false; bool need_parse; char *q, saved_c;
while (*p) { /* handle some special characters first. */ switch (*p) { case '#': /* * skip comments. * rustc may emit comments to dep-info. */ p++; while (*p != '\0' && *p != '\n') { /* * escaped newlines continue the comment across * multiple lines. */ if (*p == '\\') p++; p++; } continue; case ' ': case '\t': /* skip whitespaces */ p++; continue; case '\\': /* * backslash/newline combinations continue the * statement. Skip it just like a whitespace. */ if (*(p + 1) == '\n') { p += 2; continue; } break; case '\n': /* * Makefiles use a line-based syntax, where the newline * is the end of a statement. After seeing a newline, * we expect the next token is a target. */ p++; is_target = true; continue; case ':': /* * assume the first dependency after a colon as the * source file. */ p++; is_target = false; is_source = true; continue; }
/* find the end of the token */ q = p; while (*q != ' ' && *q != '\t' && *q != '\n' && *q != '#' && *q != ':') { if (*q == '\\') { /* * backslash/newline combinations work like as * a whitespace, so this is the end of token. */ if (*(q + 1) == '\n') break;
/* escaped special characters */ if (*(q + 1) == '#' || *(q + 1) == ':') { memmove(p + 1, p, q - p); p++; }
q++; }
if (*q == '\0') break; q++; }
/* Just discard the target */ if (is_target) { p = q; continue; }
saved_c = *q; *q = '\0'; need_parse = false;
/* * 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_source) { /* * The DT build rule concatenates multiple dep files. * When processing them, only process the first source * name, which will be the original one, and ignore any * other source names, which will be intermediate * temporary files. * * rustc emits the same dependency list for each * emission type. It is enough to list the source name * just once. */ if (!saw_any_target) { saw_any_target = true; printf("source_%s := %s\n\n", target, p); printf("deps_%s := \\\n", target); need_parse = true; } } else if (!is_ignored_file(p, q - p) && !in_hashtable(p, q - p, file_hashtab)) { printf(" %s \\\n", p); need_parse = true; }
if (need_parse && !is_no_parse_file(p, q - p)) { void *buf;
buf = read_file(p); parse_config_file(buf); free(buf); }
is_source = false; *q = saved_c; p = q; }
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);}
int main(int argc, char *argv[]){ const char *depfile, *target, *cmdline; void *buf;
if (argc != 4) usage();
depfile = argv[1]; target = argv[2]; cmdline = argv[3];
printf("savedcmd_%s := %s\n\n", target, cmdline);
buf = read_file(depfile); parse_dep_file(buf, target); free(buf);
fflush(stdout);
/* * In the intended usage, the stdout is redirected to .*.cmd files. * Call ferror() to catch errors such as "No space left on device". */ if (ferror(stdout)) { fprintf(stderr, "fixdep: not all data was written to the output\n"); exit(1); }
return 0;}