diff --git a/tar-tree.c b/tar-tree.c index 32f226ea5..37cd33692 100644 --- a/tar-tree.c +++ b/tar-tree.c @@ -1,21 +1,16 @@ /* - * Copyright (c) 2005 Rene Scharfe + * Copyright (c) 2005, 2006 Rene Scharfe */ #include #include "cache.h" #include "diff.h" #include "commit.h" +#include "strbuf.h" +#include "tar.h" #define RECORDSIZE (512) #define BLOCKSIZE (RECORDSIZE * 20) -#define TYPEFLAG_AUTO '\0' -#define TYPEFLAG_REG '0' -#define TYPEFLAG_LNK '2' -#define TYPEFLAG_DIR '5' -#define TYPEFLAG_GLOBAL_HEADER 'g' -#define TYPEFLAG_EXT_HEADER 'x' - #define EXT_HEADER_PATH 1 #define EXT_HEADER_LINKPATH 2 @@ -119,6 +114,127 @@ static void write_blocked(void *buf, unsigned long size) write_if_needed(); } +/* + * pax extended header records have the format "%u %s=%s\n". %u contains + * the size of the whole string (including the %u), the first %s is the + * keyword, the second one is the value. This function constructs such a + * string and appends it to a struct strbuf. + */ +static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword, + const char *value, unsigned int valuelen) +{ + char *p; + int len, total, tmp; + + /* "%u %s=%s\n" */ + len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1; + for (tmp = len; tmp > 9; tmp /= 10) + len++; + + total = sb->len + len; + if (total > sb->alloc) { + sb->buf = xrealloc(sb->buf, total); + sb->alloc = total; + } + + p = sb->buf; + p += sprintf(p, "%u %s=", len, keyword); + memcpy(p, value, valuelen); + p += valuelen; + *p = '\n'; + sb->len = total; +} + +static unsigned int ustar_header_chksum(const struct ustar_header *header) +{ + char *p = (char *)header; + unsigned int chksum = 0; + while (p < header->chksum) + chksum += *p++; + chksum += sizeof(header->chksum) * ' '; + p += sizeof(header->chksum); + while (p < (char *)header + sizeof(struct ustar_header)) + chksum += *p++; + return chksum; +} + +static void write_entry(const unsigned char *sha1, struct strbuf *path, + unsigned int mode, void *buffer, unsigned long size) +{ + struct ustar_header header; + struct strbuf ext_header; + + memset(&header, 0, sizeof(header)); + ext_header.buf = NULL; + ext_header.len = ext_header.alloc = 0; + + if (!sha1) { + *header.typeflag = TYPEFLAG_GLOBAL_HEADER; + mode = 0100666; + strcpy(header.name, "pax_global_header"); + } else if (!path) { + *header.typeflag = TYPEFLAG_EXT_HEADER; + mode = 0100666; + sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1)); + } else { + if (S_ISDIR(mode)) { + *header.typeflag = TYPEFLAG_DIR; + mode |= 0777; + } else if (S_ISLNK(mode)) { + *header.typeflag = TYPEFLAG_LNK; + mode |= 0777; + } else if (S_ISREG(mode)) { + *header.typeflag = TYPEFLAG_REG; + mode |= (mode & 0100) ? 0777 : 0666; + } else { + error("unsupported file mode: 0%o (SHA1: %s)", + mode, sha1_to_hex(sha1)); + return; + } + if (path->len > sizeof(header.name)) { + sprintf(header.name, "%s.data", sha1_to_hex(sha1)); + strbuf_append_ext_header(&ext_header, "path", + path->buf, path->len); + } else + memcpy(header.name, path->buf, path->len); + } + + if (S_ISLNK(mode) && buffer) { + if (size > sizeof(header.linkname)) { + sprintf(header.linkname, "see %s.paxheader", + sha1_to_hex(sha1)); + strbuf_append_ext_header(&ext_header, "linkpath", + buffer, size); + } else + memcpy(header.linkname, buffer, size); + } + + sprintf(header.mode, "%07o", mode & 07777); + sprintf(header.size, "%011lo", S_ISREG(mode) ? size : 0); + sprintf(header.mtime, "%011lo", archive_time); + + /* XXX: should we provide more meaningful info here? */ + sprintf(header.uid, "%07o", 0); + sprintf(header.gid, "%07o", 0); + strncpy(header.uname, "git", 31); + strncpy(header.gname, "git", 31); + sprintf(header.devmajor, "%07o", 0); + sprintf(header.devminor, "%07o", 0); + + memcpy(header.magic, "ustar", 6); + memcpy(header.version, "00", 2); + + sprintf(header.chksum, "%07o", ustar_header_chksum(&header)); + + if (ext_header.len > 0) { + write_entry(sha1, NULL, 0, ext_header.buf, ext_header.len); + free(ext_header.buf); + } + write_blocked(&header, sizeof(header)); + if (S_ISREG(mode) && buffer && size > 0) + write_blocked(buffer, size); +} + static void append_string(char **p, const char *s) { unsigned int len = strlen(s); @@ -237,16 +353,12 @@ static void write_extended_header(const char *headerfilename, int is_dir, static void write_global_extended_header(const unsigned char *sha1) { - char *p; - unsigned int size; - - size = extended_header_len("comment", 40); - write_header(NULL, TYPEFLAG_GLOBAL_HEADER, NULL, NULL, - "pax_global_header", 0100600, NULL, size); - - p = get_record(); - append_extended_header(&p, "comment", sha1_to_hex(sha1), 40); - write_if_needed(); + struct strbuf ext_header; + ext_header.buf = NULL; + ext_header.len = ext_header.alloc = 0; + strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40); + write_entry(NULL, NULL, 0, ext_header.buf, ext_header.len); + free(ext_header.buf); } /* stores a ustar header directly in the block buffer */ diff --git a/tar.h b/tar.h new file mode 100644 index 000000000..3467705e9 --- /dev/null +++ b/tar.h @@ -0,0 +1,25 @@ +#define TYPEFLAG_AUTO '\0' +#define TYPEFLAG_REG '0' +#define TYPEFLAG_LNK '2' +#define TYPEFLAG_DIR '5' +#define TYPEFLAG_GLOBAL_HEADER 'g' +#define TYPEFLAG_EXT_HEADER 'x' + +struct ustar_header { + char name[100]; /* 0 */ + char mode[8]; /* 100 */ + char uid[8]; /* 108 */ + char gid[8]; /* 116 */ + char size[12]; /* 124 */ + char mtime[12]; /* 136 */ + char chksum[8]; /* 148 */ + char typeflag[1]; /* 156 */ + char linkname[100]; /* 157 */ + char magic[6]; /* 257 */ + char version[2]; /* 263 */ + char uname[32]; /* 265 */ + char gname[32]; /* 297 */ + char devmajor[8]; /* 329 */ + char devminor[8]; /* 337 */ + char prefix[155]; /* 345 */ +};